“Biological Agriculture” relies on earthworms and other soil critters to do what plows and synthetic chemicals do in conventional agronomic systems.  Follow the advice below to encourage worm populations in your fields:

–>     There are many species of earthworms around the world.  The most common agricultural species in North America and Europe are the Common Garden Earthworm = Nightcrawler = Lumbricus terrestris, and the Manure Worm = Redworm = Eisenia foetida.  These are the most prevalent species sold by worm hatcheries for fish bait and farming.

–>     Nightcrawlers dig vertical burrows deep into the subsoil.  At night the worms rise to the soil surface to feed = they drag bits and pieces of leaves and other organic matter down into their tunnels.  Walk through a field at night with a flashlight and you will see many earthworms.

–>     Manure worms live close to the soil surface and do not dig vertical burrows.  Redworms are specialized to eat manure and so they are rarely seen except around the base of compost piles or in fields where many animals graze.

–>     31 nightcrawlers or manure worms per ounce; 500 worms per pound; 1,000,000 worms = 2,000 pounds = 1 ton.  1 average earthworm (Lumbricus terrestris) or manure worm (Eisenia foetida) from a commercial hatchery weighs 0.002 pound = 0.032 ounce = 0.9072 gram.

–>     Active, adult earthworms (Lumbricus terrestris) eat their body weight in soil and organic matter daily.  Sluggish worms, immature worms, and worms of other species may eat only 10% to 30% of their body weight each day.  1,000,000 common earthworms per acre (about 23 worms per square foot of topsoil 12 inches deep) = 1 ton of earthworm castings = worm manure DAILY during the growing season.

–>     Usage Note:  1 earthworm cast, 2 earthworm casts, many earthworm castings.

–>     Average daily worm cast is about 0.90 gram although weight of surface casts is considerably greater and varies widely.  Average surface cast weight is approximately 10 to 14 grams or about 0.30 to 0.50 ounce.  Surface worm cast weight ranges up to about 2 ounces in temperate climates and considerably more in tropical areas, depending on worm species, soil type, and available food.  For example, 1 average adult earthworm (2 to 3 years old) living in a bed of compost in a tropical climate can produce 10 pounds = 4.54 kilograms of castings annually ~ 12.4 grams ~ 0.43 ounce of castings daily.

–>     Average surface cast volume is approximately 1 Tablespoon = 15 milliliters (plus or minus 7 milliliters).

— >     Earthworms are most active in early spring and mid fall when weather is cool and moist.  Ideal soil temperature = 65 degrees Fahrenheit.  Earthworms are less active during hot, dry summer months.  Earthworms rise to the surface to feed at night then sound to lower soil depths each morning when temperatures rise.

–>     Do not plow in spring or fall if practical as this kills many worms.  Do not plow, cultivate, or spray in early evening, after dark, or early in the morning as this kills many worms.  The best time to till, cultivate, or spray is in the afternoon when temperatures are highest and worms have retreated to cooler soil depths.

–>     Keep fields planted with cover crops in spring and fall to feed worms.  They need much food at this time.

–>     Don’t leave soil bare over winter.  Protect winter fields with an insulating blanket of crop residues, mulch, or cover crops.  1 or 2 inches of organic matter can double earthworm populations.

–>     Earthworm populations increase in direct proportion to the amount of organic matter on the soil surface = leaves, twigs, straw, et cetera.  More cover = more protection & more food = higher worm populations.  Keep the soil mulched or covered with growing plants at all times.  2 inches of mulch double worm populations compared to cornfields where whole stalks are left on soil surface.

–>     Baby earthworms when they hatch from their cocoons = egg cases are very small, only 1/2 to 3/4 inch long.  Earthworms are extremely vulnerable when first hatched.  Do not plow, cultivate, or spray when worms are hatching.

–>     Earthworms need protein in their diet.  Worm populations double on legume fields compared to grass fields.  Earthworms especially favor clovers, particularly white clover.  Include legumes in field rotations, pastures & hay fields, cover crop mixes, and living mulches.

–>     Earthworms breed and grow very slowly.  Baby worms take 2 to 3 years to mature.  A plentiful, steady food supply is essential to support maximum breeding and population growth.  More organic matter (roots, stems, leaves) = more food = faster population growth = more worms.

–>     Earthworms do not spread rapidly.  A worm colony might spread 3 feet in a year.  That’s as fast as earthworms go.  To “seed” worms drop 6 nightcrawlers every 30 feet then immediately cover with a generous heap of mulch, compost, or manure = whatever worms are used to eating.  It takes at least 10 years for worm colonies spaced 30 feet apart to spread across an acre-sized field.  1 acre = 43,560 square feet = 4,840 square yards ~ 0.404 hectare.

–>     Adult worms are particularly sensitive to dietary changes.  For example, worms raised in hatcheries die if placed in corn fields because they have problems adapting to new, strange foods.

–>     Do not try to seed Manure Worms = Eisenia foetida in crop fields.  The manure worms will die because they are not adapted to this environment.  Use only nightcrawlers = Lumbricus terrestris for agricultural development, mine reclamation, terraforming, reforestation, and similar environmental restoration projects.

–>     If you need to seed worms, talk to the hatchery and ask for their best deal on earthworm cocoons.  Baby worms adapt quickly to any food available.  Mix egg cases gently with screened peat moss, corn meal, sifted compost, or similar carrier then “plant” with a common grain drill.

–>     Switching from conventional tillage to no-till does not happen overnight.  Conversion speed is entirely dependent on earthworm food supplies.  There is no solution for worms’ low natural reproduction rates.  Buying more worms or egg cases won’t make the process go any faster.  You can’t fix this problem by throwing money at it.  Patience is required.  You won’t see substantial improvements in soil structure or fertility until the fourth or fifth year of no-till ~ 2 earthworm generations.  Dramatic differences become smack-upside-the-head obvious by the 7th or 8th year without plows ~ 4 worm generations.  Conversion speed is controlled by how many tons of organic matter are added to each field.  Start looking at crops in terms of their biomass production.  This game is all about weight.  The farmer with the most tons wins!

–>     Tillage kills earthworms.  Loses depend on plow type, tillage depth, and time.  Chisel plows are the most destructive, disk plows slightly less so.  Old fashioned moldboard plows are the least destructive of all conventional tillage implements.  Chisel plows kill 3 times as many earthworms as moldboard plows.

–>     RULE:  Less tillage is better than more tillage.  Shallow tillage is better than deep tillage.  “Warm tillage” (afternoon & summer) is better than “cool tillage” (spring, fall, morning, evening, and night).

–>     Till just enough to get your crop in the ground.  Disturb the soil as little as possible.  All you need is a small hole to set transplants or a narrow slot to sow seeds.  It is rarely necessary to till more than 2 inches deep (unless you are planting potatoes).

–>     No-Till is better than strip till which is better than ridge till which is better than whole surface conventional plowing.

–>     Rear mounted rototillers are ideal tools for shallow tillage.  For example:  Broadcast winter wheat and Dutch White Clover = Trifolium repens into standing weeds or cover crop.  Mow vegetation then rototill only 2 inches deep to get seeds into the ground.  Irrigate to firm seedbed or wait for rain.  Your field will look rough and trashy but the litter is necessary to prevent wind and water erosion.  Some seeds will be buried too deep, others too shallow, but enough will germinate and survive to produce a good crop.  If soil is too wet, omit rototilling.  You will still make a profitable crop.  Small seeds do not absolutely need to buried in earth.  Cut weeds or nurse crop will cover and protect seed.

–>     Earthworms do not “like” to eat maize leaves and they especially dislike whole corn stalks and cobs.  Continuous corn = planting maize in the same field year after year reduces earthworm populations to minimal levels.  For best results use a stalk chopper or forage chopper to shred dead corn plants so they decompose faster.  Plant maize into a living mulch of Red Clover = Trifolium pratense or other nitrogen fixing legume.  Follow corn with fall turnips or other cover crop to feed and protect worms over winter.  Rotate corn with legumes or other broad leaf cover crops.  Do not follow maize with a grass or cereal crop unless also planted with a companion crop of clover or other legume.  Broad ecological diversity favors large earthworms populations.  Translation:  Worms like a varied, balanced diet.

Example:     Plant forage maize at 80,000 to 100,000 seeds per acre to kill weeds.  Flatten with a roller-crimper or cut with a sickle bar mower after 70 days (18 tons biomass) or approximately 110 days (30 tons biomass per acre).  This is called Mulch-In-Place.  Direct seed pumpkins or squash through the corn mulch with a no-till seeder.  At the same time, broadcast Dutch White Clover = Trifolium repens or other low growing legume over field.  Clover fills any gaps in the mulch and provides earthworms with a “balanced diet”.  Result:  95% or better weed control and few insect pests.  Mulch keeps fruits clean so farmer gets premium prices for his pumpkins.

Note:     Mulch-In-Place is used to grow crops without herbicides.  Popular mulch crops include Winter Rye = Cereal Rye = Secale cereale in temperate climates and Sunn Hemp = Crotalaria juncea in tropical and subtropical climates.

–>     Adult earthworms can live 9 or more years in captivity.  How long worms live in the wild is unknown.

–>     Worms constantly maintain their burrows which often extend 5 to 6 feet into the subsoil.  About the diameter of a pencil, worm holes are essential for aeration and drainage of natural soils.  Fields with populations of 1 million earthworms per acre typically contain approximately 900 to 1,200 MILES of tunnels.  These tubes are lined with “earthworm cement”, a natural glue that keeps tunnels open many years after resident earthworms have died.  Plant roots follow earthworm burrows deep into the subsoil where moisture levels are relatively constant.  This is why crops grown in biologically managed fields have considerable drought resistance.  (Crop roots also follow weed roots into the subsoil, especially weeds with deep taproots.  This is why melons grown in weeds make a crop in dry years while clean cultivated vines shrivel and die).

–>     If agricultural wastes are plentiful earthworms can be fed just like crop plants on an irrigation schedule.  Apply weed seed meal, spoiled corn meal, dried brewer’s grains or similar DRY organic “fertilizer” at 2 Tablespoons (1/8th cup) per square foot ~ 1 ounce per square foot ~ 5 pounds per 100 square feet ~ 1 ton (2,000 pounds) per acre.  Apply WET materials like spent brewer’s grains or fresh cow manure at 8 Tablespoons (1/2 cup) per square foot ~ 4 ounces per square foot ~ 25 pounds per 100 square feet ~ 5 tons per acre.  Broadcast worm food on soil surface.  Reapply as needed when food is eaten = no longer visible on soil surface.

–>     Ammonia based nitrogen fertilizers kill earthworms.  The worst form is anhydrous ammonia gas.  Liquid ammonia fertilizers are far less injurious.  Note:  Organic fertilizers can also be lethal.  Excessive amounts of manure lagoon effluent decimate worm populations.  It is good practice to irrigate before applying ammonia or any fertilizer, chemical or organic.  (Irrigation prevents plants from absorbing too much fertilizer at once.  Over-fed plants attract insect pests).

–>     RULE:  Chemical fertilizers (or manure lagoon effluents) are best applied in small amounts throughout the growing season, ideally diluted in irrigation water.  For best results do not apply fertilizers to bare soils; apply nutrients only to growing plants.  Earthworms are quite sensitive to concentrated chemicals, organic or synthetic.

–>     To stabilize ammonia in animal manures mix with 5% phosphate rock powder by weight (100 pounds of phosphate rock per ton = 2,000 pounds of manure).  Store under cover until needed.  Spread or incorporate manure on field then immediately seed with Buckwheat (Fagopyrum esculentum) or other phosphorous absorbing cover crop.  (Mixing phosphate rock with manure greatly increases phosphate availability to crops.  Organic acids in manure make phosphorous soluble).

–>     Concentrated chemical fertilizers (especially nitrogen) decrease soil organic matter and earthworm populations.  Spread supplementary organic matter on fields where chemical nutrients are applied.  Whenever practical use organic fertilizers to encourage earthworm growth.

–>     How Earthworm Populations Vary by Soil Type and Land Use

50,000 worms/acre ~ 1  worm/square foot:  Moldboard Plowed Continuous Corn; Acid Peat Soils.

80,000 worms/acre ~ 2 worms/square foot:  No-Till Continuous Corn with Herbicide.

150,000 worms/acre ~ 3 worms/square foot:  Fine Gravel Soils; Coarse Sandy Soils; Medium & Heavy Clay Soils.

170,000 worms/acre ~ 4 worms/square foot:  Bare Earth Orchards (Conventional Cultivation); Alluvial = Silt Soils; Light Clay Soils; Heavy Loam Soils.

225,000 worms/acre ~ 5 worms/square foot:  Medium Loam Soils; Fine Sandy Soils.

250,000 worms/acre ~ 6 worms/square foot:  Chisel Plowed Corn & Soybeans Rotation; Chisel Plowed Continuous Soybeans; Light Loam Soils.

500,000  worms/acre ~ 12 worms/square foot:  No-Till with Herbicides.

650,000 worms/acre ~ 15 worms/square foot:  Moldboard Plowed Continuous Soybeans.

1,000,000 worms/acre ~ 23 worms/square foot:  Biological No-Till (Rye Mulch-In-Place); Orchards with Mixed Grass & Legume Sod; Undisturbed Tall Grass Prairies & Hay Fields; Natural Alpine Meadows.

1,300,000 worms/acre ~ 30 worms/square foot:  Biological No-Till with Mixed Species Cover Crops; Fields Fallowed 5 Years (Mostly Broad Leaf Weeds).

2 million worms/acre ~ 46 worms/square foot:  Continuous Clover Living Mulch; Organic Gardens; Dairy Pastures; Manure Fertilized Fields (22 Tons per Acre Yearly).

3 million worms/acre ~ 69 worms/square foot:  Year-Round Mulch 8 Inches Thick (Vineyards & Berry Farms); Sheet Composting 12 Inches Thick (Orchards); High Humus Organic Gardens; Raised Beds Filled with Compost, Leaf Mold, or Manure.

4 million worms/acre ~ 92 worms/square foot:  Undisturbed Temperate Deciduous Forests with Deep Leaf Litter; Intensively Grazed Alpine Pastures.

5 million worms/acre ~ 115 worms/square foot:  Temperate Rain Forests in Oregon & Washington.

6 million worms/acre ~ 138 worms/square foot:  Intensive Rotational Grazing Dairy Pastures; Manure Fertilized Fields (44 Tons per Acre Yearly).

7 million worms/acre ~ 161 worms/square foot:  Greenhouse Beds 3 Feet Deep Filled with Composted Manure.

8 million worms/acre ~ 184 worms/square foot:  New Zealand Sheep Pastures (Intensive Rotational Grazing).

Note:     Numbers are approximate.  Expect considerable variation between countries, climatic zones, elevation above sea level, and land management practices.  Earthworms do not thrive in acidic soils, poorly drained soils, rocky or sandy soils, or tight heavy clays.  The most important environmental factor for earthworm survival is ORGANIC MATTER.  Earthworm numbers increase or decrease dramatically depending on the amount of available food.  Highest populations occur on soils where plants grow year-round, and on soils covered with substantial depths of leaf litter or other plant materials.  To estimate worm populations use a tape measure and straight-edged garden spade, dig a 1 cubic foot soil sample, then carefully break apart the soil and tally earthworm numbers.  Multiple samples per acre yield more accurate estimates.

–>     1 million earthworms per acre is the Holy Grail for most farmers.  This goal is unreachable with conventional farming practices.  To increase worm populations on a field-scale basis requires a long-term soil conservation strategy including crop rotations, cover crops, living mulches, and reduced tillage.  Additional measures such as improved drainage (vertical mulching or tile lines), increased aeration (subsoil ripping or keyline plowing), and erosion control (terraces, contour planting and strip cropping) may also be required.  Overriding all is the logistics of food supply = providing sufficient tonnage of organic matter to feed an army of earthworms and other soil critters.  This is rarely accomplished unless the soil is covered with growing plants 365 days each year.

–>     A watershed management plan is recommended as more water = more vegetation = higher earthworm populations.  The goal is to capture and store every drop of rain that falls upon your land.  Passive or active irrigation may be needed to maintain worm populations at desired levels.

–>     Reaching the goal of 2 or 3 million earthworms per acre is nearly impossible without some form of “mixed agriculture” = crops and farm animals.  Animals provide manure needed to feed large numbers of worms.

–>     Cow manure applied at 1 pound per square foot ~ 22 tons = 44,000 pounds per acre yearly is sufficient to maintain populations of 1 million earthworms per acre (on fields where plants are grown year-round = 365 days annually).

–>     Earthworm populations soar when pastures are managed by intensive rotational grazing or mob grazing.  High concentrations of livestock (300 to 1,500 Animal Units per acre per day) deposit vast quantities of manure.  Fresh manure is excellent worm food.  (1 Animal Unit = 1 AU = 1,000 pounds of live animal weight, regardless of species).

–>     The ancient Roman practice of cattle penning relies on earthworms to help restore “tired”, “weak”, or “sick” fields.  Erect temporary fencing around land to be healed.  Broadcast seed or spread wildflower hay over soil.  Fill enclosure with livestock until land is “well crowded” = animals have just enough room to turn around ~ 8 x 8 feet = 64 square feet per cow ~ 680 cows per acre.  Feed livestock in pen until land is “well dunged and trodden” = 1/2 to 1 pound of manure per square foot ~ 10 to 20 tons of manure per acre = move livestock to new pen every day or every other day.  Cattle stomp seed into earth.  Earthworms and dung beetles till soil.  Manure and urine fertilize ground.  Pastures or fields are “enlivened” = revived by intensive dose of organic matter which causes soil critter populations to soar.  Soil organisms jump start biological nutrient recycling system which supports land revegetation.  Earthworms provide natural soil restoration without tractors, diesel fuel, or synthetic chemicals.

–>     Greek philosophers first noted the link between earthworms and improved crop growth.  This observation led to the development of worm farming practiced by cottagers and other small landholders who did not have cows or draft animals to produce manure for fertilizer.  In spring spread cut weeds and other green plant materials over garden.  Apply mulch thickly = 8 inches deep.  This was the original green manure.  In fall, rake tree leaves and spread over garden 8 inches deep.  Keep garden covered with weeds and leaves year-round.

The night before planting, take a lantern and collect earthworms from hay fields or pastures.  Put worms in a pail with damp moss or leaf mold to keep the “wrigglers” from drying out.  Set several worms with each seed or transplant.  cover immediately with soil and just enough mulch to lightly shade the soil.  When plants are established tuck mulch close around their stems.  Water garden as needed.  Do not spade, fork, plow, till, hoe, or cultivate soil — just plant, mulch, and harvest.  Continuous mulch feeds and protects earthworms and topsoil.  You can run entire farms on nothing but fresh cut weeds and native earthworms.  Space rows widely so there are sufficient weeds to mulch crops liberally.

–>     Over a typical 5 to 6 month growing season, 1 million earthworms per acre will excrete 150 to 180 TONS of worm casts.  These are deposited throughout the soil profile from the surface to approximately 6 feet deep.

Note:  This is a vast amount of nutrients ~ 6.88 to 8.26 pounds of earthworm castings per square foot!  Where does all the fertilizer go?  There are far more available nutrients than any crop could possibly absorb.  This is a mystery.  Nutrient recycling must be extremely rapid with most of the fertilizer elements held within soil critters and organic matter.

–>     Fertilizer Analysis of Surface Earthworm Casts Collected Nightly for 31 Days in July 2011 from 16 Organic Farms in Austria:

2.56% Nitrogen : 1.31% Phosphorous : 1.56% Potassium: 3.69% Calcium = 51.2 pounds Nitrogen + 26.2 pounds Phosphorous + 31.2 pounds Potassium + 73.8 pounds Calcium per ton of earthworm casts.  Average organic matter content of earthworm casts sampled = 7.1% by dry weight.  50 casts bulked for each sample.  16 farms x 31 days = 496 samples total.

–>     Average Nutrient Concentration in Earthworm Casts:

5x Nitrogen (500% more N than found in parent soil)

7x Phosphorous (700% more P than found in parent soil)

10x Potassium (1,000% more K than found in parent soil)

1.5x Calcium (150% more Ca than found in parent soil)

3x Magnesium (300% more Mg than found in parent soil)

Earthworms are living fertilizer factories.  They ingest their weight in soil and organic matter daily then excrete manure containing concentrated plant nutrients.  These nutrients are highly available = easily absorbed and will not “burn” plant roots.  Earthworm casts are rich sources of essential plant micro-nutrients.  These trace elements are often “tied up” = unavailable in parent soils but highly soluble in earthworm casts.  Plants fertilized with earthworm casts rarely require additional nutrients.  This is why earthworm casts have been the standard natural greenhouse fertilizer since the 17th century.

Would You Like To Know More?     Contact the Author directly if you have any questions or need additional information about managing agricultural earthworm populations.

Please visit:  — or —  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or —  send an e-mail to:  Eric Koperek =

About The Author:     Mr. Koperek is a plant breeder who farms in Pennsylvania during summer and Florida during winter.  (Growing 2 generations yearly speeds development of new crop varieties).










What Is It?     Living mulches are cover crops grown to control weeds without herbicides or mechanical cultivation.  Seeds or transplants are set through the living mulch using no-till equipment.  Alternatively, fields can be planted by hand.  The best living mulches are low-growing nitrogen fixing legumes like Dutch White Clover (Trifolium repens).  Tall-growing legumes like Lucerne = Alfalfa (Medicago sativa) or Biennial Yellow Sweet Clover (Meliotus officinalis) also make good living mulches if managed carefully.

I’ve been working with Red Clover (Trifolium pratense) the past 40 years because the seed is less expensive than Dutch White Clover (Trifolium repens).  Sweet corn, popcorn, flint corn, flour corn, pod corn, dent corn, and oil corns all grow well when planted with standard red clover or medium red clover.

How To Do It:     Any type of maize can be top seeded = over seeded with red clover at the last cultivation.  The corn plants are tall enough (about 2 feet high) so that competition with the living mulch is minimal.

Rule-Of-Thumb:     Top seed = over seed maize with tall varieties of clover when corn plants have 4 to 8 leaves = 18 to 24 inches tall.  Maize should be 12 inches high before over seeding with Crimson Clover (Trifolium incarnatum), Sub Clover (Trifolium subterraneum), Dutch White Clover (Trifolium repens) or other types of low growing legumes.

Mow Low & Keep On Mowing:     Any type of maize can be seeded directly into standing red clover using a no-till planter with a fluted coulter.  Two weeks later the field should be closely mowed with a swathing board and divider to keep the clover from falling on the planted rows of corn.  Alternatively, clover can be mowed directly before seeding.  Watch regrowth carefully; a second mowing may be required 2 weeks later.  No herbicides are needed if maize is planted into standing clover; nitrogen fertilizer is not required if clover has grown on the land for 1 or more years.

Feed & Water Liberally:     Corn is sensitive to drought, especially during pollination and when ears are filling out.  For highest yields apply 1 to 2 inches of water weekly to prevent moisture competition between crop and living mulch.

Always remember that 2 crops are growing on the same field at the same time:  The mulch crop and the cash crop.  Careful management is required or both crops may fail.  Fertilize and irrigate generously to reduce competition between crops.

Sweet Corn Yields:     Planting hybrid sweet corn into standing red clover yields about 415 sacks per acre on average when sweet corn is seeded 8 inches apart within rows and 30 inches between rows = 25,979 seeds per acre.  Actual plants per acre ~ 21,000 (17% field loss rate is common).  1 sack = 52 ears = 4 baker’s dozen.  1 baker’s dozen = 13 ears.  415 sacks = 1,660 baker’s dozen = 21,580 marketable ears per acre.  Note:  Yield figures are discounted 50% for typical losses to crows, deer, groundhogs, coons, ear worms, under size or poorly pollinated ears, and other causes.

Critter Control:     Raccoons (Procyon lotor) are a big problem in my area; unprotected fields are ravaged.  It is not uncommon to have 50 coons in a field of sweet corn each night.  To control coons, I use battery powered radios set to all-talk stations.  Move the radios to a different location every day.  As a last resort, dissolve 1 level teaspoon = 5 milliliters of Blue Streak Fly Bait in 1 can of regular Coca Cola and pour contents into a shallow bowl.  Set bait dishes along field boundaries to intercept coons before they get into the corn.  Note:  Blue Streak is a powerful poison that will kill any animal that ingests it.  Make sure to tie up your farm dogs to keep them safe.

Ideally, sweet corn fields should be protected with deer fencing.  If this is not practical, enclose fields with a low barrier just high enough to contain hounds.  Each field needs at least 4 deer hounds or similar large breed for adequate security.  Small breeds or lone dogs are likely to get mobbed by browsing deer that travel in herds of 40 or more animals.

Mulch-In-Place:     Buying and spreading mulch is too expensive for field scale agriculture.  It is far less costly to grow a mulch crop on the field needing weed control.  When mature, the mulch crop is killed by roller-crimping or mowing with a sickle-bar mower.  No-till equipment is then used to set seeds or transplants directly through the dead surface mulch.  Dutch White Clover (Trifolium repens) or other low growing legumes can be over seeded at the same time cash crops are planted.  Small clover seeds fill any gaps in the mulch aiding weed control and increasing field biodiversity.

Most mulch-in-place crops are cereals because grass plants decompose more slowly than broad leaf species.  4 to 5 tons = 8,000 to 10,000 pounds of long straw per acre are needed to provide 90% weed control in field crops.  Sow Common Cereal Rye = Winter Rye (Secale cereale) at 3 bushels per acre.  Roller-crimp or sickle bar mow when rye reaches 6 feet high or when seeds reach the soft dough stage.  Transplant or seed cash crop immediately.  Rye mulch provides effective weed control for 6 to 8 weeks; this is sufficient time for crop to establish and start to close the leaf canopy over the field.  Once crop canopy closes any weeds in the field will be shaded and minimally competitive.

Weed Farming:     It is possible to grow maize in weeds although this requires careful management.  Select a field with dense, luxuriant weed growth at least 3 feet tall (5 or 6 feet high is better).  Broadcast Dutch White Clover (Trifolium repens) or other low-growing legume into standing weeds.  Kill weeds with a sickle bar mower or flatten with a roller-crimper.  Seed maize with a no-till planter when the soil is warm = at least 65 degrees Fahrenheit.  Irrigate immediately or wait for rain.  You are now in a race against time.  Watch field diligently for corn germination and weed density.

It may be necessary to mow field 2 weeks after seeding if surface mulch is not thick enough to suppress weed growth.  Mow field as close to the soil surface as practical.  If weeds regrow quickly, mow field again 2 weeks later.  Adjust mower height to prevent killing corn seedlings.

The trick here is to germinate the corn as fast as possible — which is why irrigation is so profitable.  If maize seedlings have a few days head start over the weeds they will make a good crop.

The secret to weed farming is to manage wild plants just like any other mixed species cover crop.  Fertilize and irrigate weedy fields to encourage maximum growth.  More biomass (leaves & stems) = more mulch and better weed control.

Maize Polycultures:     Planting corn, beans, and squash together in the same field is rarely practiced nowadays because interseeding is difficult to mechanize successfully.  Consequently, most traditional polycultures are seeded by hand.

Space maize widely so beans and squash get enough light to make a crop.  40 inches between rows and 12 inches between plants within each row is traditional practice = 62 rows x 208 plants per row = 12,896 plants per acre ~ 3.3 square feet per corn plant.

Use a lawn mower to clip living mulch before seeding beans and squash.  Alternatively, wait until the last cultivation (when corn plants are 2 feet tall) then over seed field with Dutch White Clover (Trifolium repens) directly beans and squash are planted.

Wait until soil temperatures reach at least 65 degrees Fahrenheit and corn plants have 8 leaves ~ 24 inches high before planting pole beans and squash.  Earlier plantings are rarely successful because beans and squash overrun short maize stalks.  Soak bean and squash seeds in warm water overnight to speed germination.  Plant 2 or 3 beans close to each corn stalk.  Thin later to 1 strong seedling per maize plant = 12,896 pole bean plants per acre.  Seed squash every other corn row and 6 feet between plants within row = 31 rows per acre x 34 plants per row = 1,054 squash plants per acre.  Irrigate immediately beans and squash are planted.

Strip Cropping:     Strip cropping combines the pest control advantages of polycultures with the efficiency of modern farm machinery.  The idea is to divide farms or fields into long, narrow strips 4 to 16 rows wide depending on the crop and available machinery.  Like ribbons each strip wends its way across the countryside following land contours.  Strips on either side are planted with unrelated crops.  Long fields are good for mechanical efficiency (fewer turns) while narrow fields maximize biological edge effects (fewer pests).

For example, instead of growing corn, soybeans, sunflowers and alfalfa in separate fields plant each crop in narrow strips:  4 rows of corn + 4 rows of soybeans + 4 rows of sunflowers + 4 rows of alfalfa.  (Try to make each strip about the same width).  Repeat this pattern across the field or over the entire farm.  Note how tall and short crops are alternated for better light penetration.  Legumes are paired with non-legumes.  Each crop is unrelated to its neighbors.

Growing different row crops close together mimics the biological diversity of companion planted gardens and traditional polycultures.  Translation:  Insect pests go somewhere else for lunch.

Build-A-Toy:     No-till equipment is costly.  If you are mechanically minded you can build an inexpensive no-till seeder in your own garage.  At minimum, you need 5 things:  (1)  A large (20 inches or more in diameter) coulter with a razor sharp edge to cut through standing vegetation.  You can use a fluted coulter at your discretion.  (2)  Adjustable depth 3/4 inch or wider blade to open a slot for seeding.  A fertilizer knife, cultivator shovel, or chisel tine can be used for this application.  (3)  A delivery tube to drop seed into opened soil.  Tube can be any convenient dimension (up to 3 or 4 inches diameter to plant potatoes or set transplants).  (4)  Double press wheels to ensure good seed-to-soil contact.  (5)  Removable iron weights to adjust planter mass so coulter cuts through surface trash and seeding knife penetrates the soil.  Other items can be added to the basic rig as needful.  For example, add a seat then a child can manually drop seeds, potatoes, or transplants.

Would You Like To Know More?     Please contact the Author directly if you have any questions or need additional information about growing maize in living mulches.

Please visit:  — or —  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or —  send an e-mail to:  Eric Koperek =

About The Author:     Mr. Koperek is a plant breeder who farms in Pennsylvania during the summer and Florida during winter.  (Growing 2 generations each year speeds development of new crop varieties).















What works, what doesn’t, and what to do if you can’t spray.

The guy who invents a safe alternative to Roundup will earn millions!  Right now, there is a distressing lack of alternatives to glyphosate = Roundup.  Below is a short summation of available organic vegicides and alternative weed controls.  Choose the best formula or method for your farm.  Experiment until you obtain the degree of weed control desired.

HERBICIDE SCIENCE:     All organic herbicides work by desiccation = leaves dry out = plant death is caused by water loss.  Thus, organic herbicides perform reasonably well on ANNUAL broadleaf weeds and grasses, especially young plants less than 30 days old or 6 inches high.  Desiccant kill rates on young annuals or perennials normally range from  80% to 100%.  Mature perennial weeds (with long tap roots) and perennial grasses (with growing points below soil surface) are rarely killed by desiccant herbicides because these are contact chemicals only — the herbicide is NOT translocated to roots or other underground parts of the plant.  Spraying a desiccant herbicide will knock back perennial weeds (by burning down exposed foliage) but will not kill established plants.  Repeated applications are necessary to control perennial weeds; this is rarely economic so herbicide use must be integrated with other cultural practices to obtain desired level of weed control.  This often means rethinking how to grow and harvest crops.

COMMON LYE:     The cheapest burn-down herbicide is old fashioned lye; either sodium hydroxide (NaOH) or potassium hydroxide (KOH) works equally well.  Powdered sodium lye (for example, Red Devil Lye) is a special order industrial chemical that requires a signed application statement (because sodium lye is used to make illegal drugs).  You can make your own potassium lye at home simply by leaching wood ashes with water.  If a fresh egg floats in the solution, the lye is strong enough to kill plants (or make soap).

Potassium Lye Formula by Weight:     Prepare a 45% to 50% concentration by weight of water = 0.45 to 0.50 expressed as a decimal.  Note:  1 U.S. gallon of water weighs 8.34 pounds = 3.78 kilograms.  0.45 x 8.34 pounds per gallon of water = 3.753 = 3 3/4 pounds of wood ashes per gallon.  Sift wood ash through window screening before weighing.  Mix ash and water the night before use then strain most carefully before application.

Potassium Lye Formula by Volume:     Combine 2 parts finely sifted wood ashes with 3 parts water by volume.  Mix ashes and water then let stand overnight before use.  Decant and filter wood ash lye through paper coffee filters to avoid clogging lines and spray nozzles with grit.

All herbicides are more effective if a spreading-sticking agent is mixed with the solution.  To increase weed kill rates, combine lye with 2% commercial surfactant (surface active agent) by weight or volume.  The admix helps lye solution cover and grip foliage.  If commercial surfactant is not available, substitute an equal portion of common liquid dishwashing detergent.  Addition of 2% “Polysorbate-20” (a powerful emulsifier)  makes herbicide mixtures even more deadly by stripping away protective wax coatings on plant cell walls.

>>>  Concentrated lye solution can have a pH near 14 = it’s extremely caustic = highly basic = will change soil pH if used continuously or in high volumes.  Lye herbicide is NOT recommended for use around acid-loving plants like potatoes, raspberries, cranberries, blueberries, strawberries, azaleas, laurels, rhododendrons, pine trees or other conifers (plants with needle or scale-like leaves that bear seeds in cones).  Check soil pH regularly; it may not be necessary to apply agricultural lime to fields where lye herbicide is used frequently.

>>>  Where agricultural lime is too costly, spraying sodium or potassium lye solution is a cheap way to adjust soil pH.  For example:  To bring highly acid soils into production, spray lye then plant beans.

>>>  Substitute wood ashes where agricultural limestone is unavailable or expensive.  Swap 2 parts wood ashes by weight or volume for every part of powdered limestone.  Sift wood ash through window screening before use.  Crush charcoal screenings to pass 1/4 inch hardware cloth sieve then compost with an equal or greater volume of fresh manure before applying to garden or field.

MALEIC HYDRAZIDE is a chemical growth regulator commonly used to keep potatoes from sprouting in storage, and tobacco plants from suckering.  Maleic hydrazide is NOT an herbicide in the conventional sense of the word (although it does kill plants if used in high concentration).  Use maleic hydrazide to SLOW weed growth; sprayed weeds are stunted rather than killed.  Weeds are knocked back just enough to give crop plants a competitive advantage.  Translation:  If weeds are dwarfed then there is no need to kill them.

Never use the word “herbicide” when talking or writing to the Government about maleic hydrazide.  The official viewpoint is that maleic hydrazide is a plant growth regulator, NOT an herbicide.  Use the word “herbicide” and you may end up having to submit a ton of regulatory paperwork!

Maleic Hydrazide Formula by Volume:     Commercial maleic hydrazide is sold as a 30.3% concentrated solution by volume containing 2.25 pounds of chemical in 1 gallon of water (26.97841% concentration by weight).  Apply 1 to 1.33 gallons of chemical solution in 30 gallons of water per acre to control sprouting in potatoes.  This manufacturer recommended concentration gives you a place to start.  [2.25 pounds chemical per gallon of commercial concentrate / 220.2 pounds of water (30 gallons) in spray tank] x 100 = 0.89928% concentration by weight.  Adjust vegicide concentration until desired level of weed control is obtained.

Maleic Hydrazide Formula by Weight:     To stunt both annual and perennial broadleaf weeds and grasses, apply 0.6% pure maleic hydrazide by weight = six tenths of one percent = 0.6 / 100 = 0.006 expressed as a decimal.  For example:  0.006 x 1,000 grams per liter of water = 6 grams of maleic hydrazide per liter or approximately 0.21 scale ounce per quart of water (6 grams / 28.35 grams per ounce = 0.2116402 scale ounce = 0.21 scale ounce or about 1/5th scale ounce of maleic hydrazide per quart of water).  This concentration will control (don’t say kill)  even multiflora rose and other invasive shrubs and trees.  Maleic hydrazide is fast becoming a favorite weed control chemical because it is safe to handle, cheap, and effective.

AMMONIUM NONANOATE is a synthetic chemical, a detergent-like surfactant that kills weeds by dissolving the wax coating on cell walls.  Damaged cells leak water = weeds die of dehydration.  Think of ammonium nonanoate as a strong soap solution; wear rubber gloves and protective goggles to keep chemical off skin and away from eyes.  Spray herbicide at night to avoid harming most beneficial insects.

Soaps, detergents, and other surface active agents = surfactants kill insects by clogging their breathing tubes.  Soap-sprayed insects die of suffocation.  Thus, it is best to spray ammonium nonanoate and other herbicidal soaps at night to avoid killing as many beneficial insects as possible.

Ammonium Nonanoate Formula by Weight:     Ammonium nonanoate is sold as a 40% concentrated solution by weight.  Mix not more than 6% by weight of commercial concentrated solution in 1 gallon of water = 2.4% by weight of ammonium nonanoate in 1 gallon of water.  1 U.S. gallon of water weighs 8.34 pounds = 3.78 kilograms.  6% = 6 / 100 = 0.06 expressed as a decimal.  0.06 herbicide concentrate x 8.34 pounds per gallon of water = 0.5004 pounds of herbicide concentrate x 16 ounces per pound = 8.0064 = 8 scale ounces of commercial concentrate in 1 gallon of water.  (This is approximately equal to 8 fluid ounces or 1/2 cup of ammonium nonanoate concentrate in 1 gallon of water).

Note:  This chemical is not currently approved for use on organic farms in the United States.  Ammonium nonanoate is a type of industrial strength soap.

SODIUM LAURYL SULFATE (SLS) is a synthetic detergent commonly found in shampoo, toothpaste, and household cleaning products.  Sodium lauryl sulfate is a contact herbicide that works by stripping the wax coating from cell walls = leaves lose water then plants die of dehydration.  As with any strong soap, wear rubber gloves (to prevent skin from drying out) and safety goggles (to keep detergent out of eyes).

Sodium Lauryl Sulfate Formula by Weight:     Mix 5% to 20% dry chemical by weight in pure water.  1 U.S. gallon of water weighs 8.34 pounds = 3.78 kilograms.  5% = 5 / 100 = 0.05 expressed as a decimal.  0.05 chemical concentration x 8.34 pounds per gallon of water = 0.417 pounds of SLS x 16 ounces per pound = 6.672 = 6 2/3 scale ounces of sodium lauryl sulfate per gallon of water (minimum concentration).  20% = 20 / 100 = 0.20 expressed as a decimal.  0.20 chemical concentration x 8.34 pounds per gallon of water = 1.668 pounds of SLS x 16 ounces per pound = 26.688 scale ounces = 1 pound 10 2/3 scale ounces of sodium lauryl sulfate per gallon of water (maximum concentration).

Sodium Lauryl Sulfate Formula by Volume:     For commercial concentrated solutions, mix 20% concentrate by volume with water.  1 U.S. gallon = 128 fluid ounces = 4 quarts = 8 pints = 16 cups = 256 Tablespoons = 768 teaspoons.  20% = 20 / 100 = 0.20 expressed as a decimal.  0.20 SLS concentrate x 768 teaspoons = 153.6 teaspoons = 51.2 Tablespoons = 3.2 cups = 1 1/2 pints + 3 Tablespoons + 2/3 teaspoon = about 3 1/4 cups herbicide concentrate in 1 gallon of water.  Another way to figure this is:  128 fluid ounces per gallon x 0.20 herbicide concentration = 25.6 fluid ounces of herbicide concentrate needed  / 8 fluid ounces per cup = 3.2 cups = about 3 1/4 cups of SLS concentrate per gallon of water.

SLS Application Rate per Acre:     Apply 2.5 gallons to 7.5 gallons of diluted herbicide per thousand square feet of farm or garden = 109 gallons to 327 gallons per acre.  Note:  Herbicidal soaps are much more effective when powerful emulsifiers and surfactants are added to the mix.

>>>  There are many different kinds of herbicidal soap.  All work the same way and should be diluted to the same concentration:  5% to 20% dry chemical by water weight, or 20% liquid concentrate by volume.  Adjust concentration and application rate as needed to kill target species.  Weeds with hairy or waxy leaves are harder to kill than less protected plants.

D-LIMONENE:     Citrus rinds contain volatile essential oils (orange oil, lemon oil, grapefruit oil, et cetera).  The largest chemical component of all citrus oils is d-limonene, a fragrant chemical and powerful surface active agent = surfactant that quickly dissolves fats, oils, and waxes.  D-limonene is a common ingredient in most natural home cleaning products.  D-limonene is also used to wash greasy automobile parts and as a safe replacement for mineral spirits (petroleum turpentine).  Use d-limonene just like any other strong detergent (ammonium nonanoate or sodium lauryl sulfate, for example).  All herbicidal soaps work by dissolving the waxy coating on plant cell walls.  Damaged leaf cells leak water then plants die of dehydration.

Pure D-Limonene Formula:     Mix 55% d-limonene by weight in water.  Mix 50% orange oil (or other citrus oil), clove oil, cinnamon oil, or lemongrass oil by weight in water.  Essential oil concentration can be decreased to 30% by weight if Polysorbate-20 (emulsifier) and spreading / sticking agent (surfactant) are added to the herbicide solution.

D-Limonene Formula with Emulsifier & Surfactant:     Combine 30% limonene + 10% emulsifier (Polysorbate-20) + 10% commercial surfactant (wetting agent) + 50% pure water = 100% total by weight or volume.  Use baking soda to adjust solution pH to 5 or above.  Apply up to 100 gallons (approximately 400 liters) of diluted herbicide per acre (about 0.40 hectare).

D-limonene can also be used in small quantities as a surfactant (spreading / sticking agent) in other herbicide or insecticide formulations.  Add one-eighth percent to one-quarter percent = 0.125% to 0.25% = 0.00125 to 0.0025 expressed as a decimal = 1 to 2 pints per 100 gallons or approximately 2.5 milliliters per liter of water.

D-limonene makes an economic herbicide provided you live near an orange juice processing plant.  Prices rise as distance from citrus groves increases.

ACETIC ACID = VINEGAR:     For commercial farms concentrated vinegar = 10% to 20% acetic acid is required.  For household gardens, common white table vinegar (5% acetic acid) will suffice.  Strong acids (concentrated vinegar) and strong bases (sodium or potassium lye) both kill weeds by rupturing cell walls = leaves leak water till plants die of thirst.

Vinegar Herbicide Formula by Weight for Farming:     Combine 20% acetic acid (liquid) + 5% citric acid (powder) + 2% commercial surfactant (spreading / sticking agent) + 73% pure water = 100 total parts by weight.  Note:  To save freight costs, order glacial acetic acid = pure, undiluted acetic acid in 1 gallon glass bottles.  Mix 1 gallon of glacial acetic acid with 9 gallons of water to make 10 gallons of concentrated vinegar (10% acetic acid) solution.  Mix 1 gallon of glacial acetic acid with 4 gallons of water to make 5 gallons of concentrated vinegar (20% acetic acid) solution.

Vinegar Herbicide Formula by Volume for Gardening:     Combine 5 cups of common white vinegar (5% acetic acid) + 1 cup of bottled lemon juice (3% to 8% citric acid) + 4 Tablespoons of dish washing detergent (to help herbicide stick to leaves) = 6 1/4 total cups by volume.

For best results, spray on a warm, sunny day when weed leaves are dry.  Apply herbicide solution generously so that leaves are thoroughly wet.

Caution!  Concentrated vinegar is a hazardous chemical, a strong acid that will burn skin and eyes.  Wear rubber gloves and safety goggles.  Do not breathe concentrated vinegar vapors.  Work outdoors with the wind at your back = blowing away from you.  Wash skin or eyes with pure, distilled water if necessary.

CHELATED IRON:     FeHEDTA (Iron-Hydroxy-Ethylene-Diamine-Triacetic-Acid) in high concentrations (26.5% by weight) will kill broadleaf weeds in turf grasses.  This herbicide works well but is most costly = far too expensive for agricultural use.

SUNFLOWER SEED HULLS:     Some plants produce natural herbicides.  Sunflower seed shells can be used as mulch to retard weed growth.  Apply 1 to 2 inches of sunflower seed hulls around ornamental or edible plants.  Note:  Herbicidal effect may inhibit growth of flowers and crops!  Perform small plot trials before spreading large amounts of sunflower hulls.

BLACK WALNUT HULLS & WOOD CHIPS:     Black walnuts produce natural herbicides that kill some plants but not others.  For example:  Tomatoes are severely stunted or killed by walnut herbicide.  Test ornamental or crop plants first before spreading mulch of black walnut hulls or black walnut wood chips.

SMOTHER CROPS:     Plants that grow faster than weeds and cast dense shade make ideal smother crops.  Multiple smother crops (planted in sequence) are often used to clear especially weedy fields or to eradicate hard-to-kill perennial weeds with deep tap roots.  For best results, do not plow fields after growing smother crops; tillage stimulates weed germination.  Broadcast small grains or turnips over standing vegetation then immediately mow or roll to cover and protect crop seed.   Alternatively, mow or roll smother crop then set seeds or transplants through surface mulch using no-till equipment.  If smother crop is tilled into the ground (as a green manure) immediately broadcast clover or other legume seed to blanket field as a living mulch.  Fields must be covered with useful plants at all times or weeds will regain foothold.  Popular smother crops include Buckwheat (Fagopyrum esculentum) and Sudangrass (Sorghum sudanense)  in temperate climates, and Sunn Hemp (Crotalaria juncea) in tropical and semi-tropical zones.

Buckwheat Smother Crop:     Fagopyrum esculentum grows 0.75 to 1.25 inches per day reaching a mature height of 50 inches (3 tons of dry matter per acre) in 6 to 8 weeks.  Blooming starts around 32 days and seeds mature in 10 to 12 weeks.  Mow, crimp, or rototill buckwheat when plants are in full bloom, about 60 days after planting.  Do not let plants mature and drop seeds or buckwheat will become a weed in the following crop.  Seed 32 to 40 pounds per acre for small seeded varieties; 50 to 72 pounds per acre for large seeded varieties.  Ideal plant population is 700,000 plants per acre = 16 seeds per square foot.  Test weights vary from 44 pounds (large seeds) to 52 pounds (small seeds) per bushel.  Approximate seed weight varies from 29 to 37 grams (1.02 to 1.30 scale ounces) per 1,000 seeds = 12,200 (large seeds) to 15,600 (small seeds) per pound.

Sudangrass Smother Crop:      Sorghum sudanense grows fast and produces natural herbicides.  Translation:  Weeds are overwhelmed.  Sudan grass grows 1/2 to 2 inches daily if soil is warm and moist.  For best results sow when soil temperatures reach 65 degrees Fahrenheit ~ 18 degrees Centigrade and irrigate with 1 to 2 inches of water weekly.  Broadcast 30 to 50 pounds, drill 35 pounds, or precision seed 13.5 pounds of pure, live seed per acre.  Average seed weight ~ 42,300 seeds per pound.  Plant seeds 1/2 to 1 1/2 inches deep in rows 7 to 14 inches apart.  Under ideal conditions Sudan grass can reach 8 to 9 feet mature height in 8 to 10 weeks.  If temperature and moisture are unfavorable, Sudan grass may take 80 to 100 days to mature.  If desired, Sudan grass may be mowed about 55 days after seeding when plants are 20 to 30 inches tall.  Leave 8 inches of stubble to help grass regrow quickly.  In temperate climates Sudan grass may be cut 2 or 3 times yearly.  6 to 8 cuttings are possible in tropical and sub-tropical areas if soil is fertile and water plentiful.  For each cutting expect 2 to 3 tons of green mulch per acre at 70% to 75% moisture content.  Expect 10 to 12 tons of green chop per acre each year under average conditions.  Under ideal conditions annual production may reach 16 to 24 tons (fresh weight) ~ 4,000 to 6,000 pounds dry weight per acre.

Sudan grass has an enormous fibrous root system that can penetrate 6 to 8 feet into the subsoil.  This huge mass of organic matter restores life and productivity to “tired soils” and “sick fields”.  Sudan grass is one of the best cover crops for weed control and soil improvement.

Sunn Hemp Smother Crop:     Crotalaria juncea is a fast growing nitrogen fixing legume.  In temperate regions with 90 or more days of warm weather, Sunn Hemp grows 1 to 1 1/4 inches per day, reaching 6 feet high and flowering approximately 60 to 70 days from seeding.  In tropical climates some varieties of Sunn Hemp grow over 20 feet tall.  Broadcast 20 to 50 pounds or drill 15 to 40 pounds of pure, live seed per acre in 6 to 36 inch rows.  For precision seeders, use a 60-cell small sugar beet plate and plant 9 pounds per acre in 15 inch rows, or 5 pounds per acre in 30 inch rows.  (Remember to inoculate seed with nitrogen fixing cowpea rhizobia).  Sow seeds 1/2 to 1 inch deep.  Average seed weight = 18,000 to 35,000 seeds per kilogram ~ 15,000 to 33,000 seeds per pound.  Average test weight = 60 pounds per bushel.  Sunn Hemp is amazingly productive when planted in moist, fertile soils.  Expect 8 to 18 tons of green mulch (4 to 9 tons dry weight) per acre at 50% moisture content 10 to 12 weeks after seeding.  Under average conditions Sunn Hemp yields 6.25 to 7 tons of green chop in 60 days = weeds are buried under a great mass of stems and leaves.

There are many aggressive, rapid-growth plants suitable for smothering weeds.  Forage Radish (Raphaus sativus variety longipinnatus) and Forage Maize (Zea mays) are two additional examples.  Choose species and varieties best adapted to local soil and climate.

COMMON CEREAL RYE:     Grain rye (Secale cereale) produces natural herbicides.  The best way to employ this herbicidal effect is to grow a 5 to 6 foot high cover crop of rye and then cut it down with a sickle-bar mower (or use a roller-crimper) when the grass starts to flower or no later than the soft dough stage of seed development.  Leave cut rye straw where it falls.  Set pumpkins or other transplants through the rye mulch.  Alternatively, use a no-till seeder with a fluted coulter to plant through the mulch.  If desired, Dutch white clover (Trifolium repens) can be broadcast over the field the same day crops are transplanted.  Clover seedlings fill any gaps in the mulch providing 90% or better weed control under average field conditions.

You can run a 25-acre vegetable farm with nothing more than a common lawn mower and a hand-cranked cyclone seeder.  Broadcast lawn clover everywhere then transplant into the living mulch.  I can’t think of an easier way to operate a truck farm or market garden.

DUTCH WHITE CLOVER:     Trifolium repens is NOT herbicidal but it does make a good living mulch that can provide effective weed control in transplanted crops and winter grains.  Dutch white clover only grows 6 to 8 inches tall so it makes an ideal living mulch for any crop that grows a foot or more high.  For best results, transplant crops directly into standing Dutch white clover.  If desired, clover can be mowed first to give transplants a little more time to get established.  Sow clover at the same time that you plant winter wheat, barley, oats, and rye.  If convenient, Dutch white clover can be broadcast over established crops when they are young (6 to 8 inches tall) or later in the season (a few weeks before harvest).  Note:  If Dutch clover seed is not available substitute Crimson Clover (Trifolium incarnatum), Sub Clover (Trifolium subterraneum), or a low-growing variety of Medium Red Clover (Trifolium pratense).  A good stand of clover will blot out most competing plants providing 90% or better weed-free fields.

OVERLAPPING ROTATIONS:     Sometimes called “interseeding”, this technique uses the competitive ability of crop plants to suppress weeds.  The idea is to top seed the following crop several weeks before the previous crop is harvested.  This gives crop seeds time to germinate and become established.  When the overstory nurse crop is harvested, the understory crop already has at least 2 weeks head start over competing plants.  In nature, possession is 9 tenths of the law; the first population established will predominate.  By overlapping rotations, weeds never get a toehold.

Successful weed control requires careful timing, zero tillage, pelleted seed, and Dutch white clover (Trifolium repens) living mulch.  Always overseed at least 2 weeks before harvest so seeds have time to germinate ahead of any weeds.  Never disturb the soil for any reason; any tillage will encourage weed growth.  Always use pelleted seed; coated seeds have better germination and seedling survival.  Always use Dutch white clover to check weed growth; clover replaces herbicides and mechanical cultivation.  One last important detail:  Return all crop residues to the field and scatter randomly to form a thin, open mulch; a light blanket of straw or leaves is necessary to protect seedlings and feed the soil.

Rice-Winter Grain & Clover Rotation:     This is the basis of Masanobu Fukuoka’s “Do Nothing Farming” system.  [See:  The One-Straw Revolution, Rodale Press, 1978].  (1)  In fall, sow pelleted winter barley or winter rye seed with Dutch white clover.  (2)  A few weeks before winter grain harvest, broadcast pelleted rice seed over standing winter cereal.  (3)  Immediately after harvesting winter grain, scatter straw randomly over field to protect germinating rice seedlings.  (4)  A few weeks before rice harvest, top seed pelleted clover and winter rye or winter barley over standing rice.  (5)  Immediately after rice harvest, scatter rice straw randomly across field to protect germinating winter grain seedlings.  (6)  Repeat rotation indefinitely; the system works with any kind of summer and winter grain.  Choose crops to fit growing season length.  Note:  Continuous cereal rotations with understory clover companion crops place severe competitive pressures on native weed species.  Provided ground is not tilled, fields remain 95% weed free without herbicides or any other weed control methods.

Hogs make great rototillers provided they do not have rings in their snouts.  Ringed hogs cannot root.

Clover-Wheat-Turnips Rotation:     15th century Dutch farmers combined free-range pig ranching with no-till agronomy to make a low-cost sustainable agriculture system called the Clover-Wheat-Turnips Rotation:  (1)  Enclose a field of Dutch white clover.  (2)  Turn pigs loose in fenced pasture.  Pigs will uproot clover eliminating need for plowing and harrowing.  (3)  Broadcast wheat seed onto pig tilled earth.  (4)  Drive sheep back and forth across field; sheep will stomp wheat seeds into ground.  (5)  When wheat starts to head out, overseed grain with turnips.  (6)  A few weeks before turnip harvest broadcast clover seed over field.  Clover protects and fertilizes soil until cycle repeats in spring.  This rotation reliably yields 40 bushels of wheat (2,400 pounds) per acre = 2,694 kilograms per hectare under European weather conditions without irrigation, diesel fuel, synthetic fertilizer, herbicides, insecticides, or fungicides.

Overlapping crop rotations are remarkably stable — farmers have been using legume-grain-root crop rotations for 700 years.  Many other rotations are possible, with or without livestock or machinery.  Choose cash crops most suited to your local soil and climate.  Use cover crops or forage crops to fill any gaps in the planting season.  Soil must be covered with growing plants at all times = 365 days yearly.  As long as continuous vegetation is maintained fields will remain 95% weed free and crop yields sustained indefinitely.

MULCH-IN-PLACE:     It is impractical to mulch large fields by hand because the volumes required are too large.  The solution is to grow a mulch crop then kill it by mowing or crimping.  Seeds or transplants are then set through the surface mulch using no-till equipment specifically designed to work in high-residue “trashy” fields.  Alternatively, harvest the mulch crop with a silage chopper then apply with a mulch spreader; this technique is ideal for orchards, vineyards, nurseries, and berry plantations where labor costs are high.

The best mulch crops are quick growing grasses that yield high-tonnages per acre.  Grasses are preferred because straw decomposes slowly and forms a nearly impenetrable mat that blocks light and prevents weed emergence.  Fields need at least 4 to 5 tons = 8,000 to 10,000 pounds of straw mulch to obtain 90% weed control.  A 5 to 6 foot stand of grain rye (Secale cereale) produces 4 to 5 tons of long straw which forms a thick, weed-blocking blanket over the soil.  Forage maize (Zea mays) is even better:  It grows 12 to 15 feet high and produces 18 tons = 36,000 pounds of mulch in only 70 days from seeding to harvest.  100 to 120 day forage maize yields up to 30 tons = 60,000 pounds of mulch per acre.  30 tons of corn stalks per acre will obliterate any weed problem for 2 seasons or longer.  Top seed maize mulch with a low growing clover and fields will remain at least 95% weed free.

ZERO INPUT AGRICULTURE:     There are many terms for this technique (No-Kill Cropping, Natural Farming, Do Nothing Agriculture, Zero Budget Natural Agriculture, Minimum Effort Agronomy, Minimal Energy Agriculture, Zero Petroleum Agriculture, et alia).  The idea is to plant seeds into standing vegetation without tillage, herbicides, fertilizers, irrigation, or any other input.  Crops (usually small grains like wheat, oats, barley, and rye) can be sown directly into pastures, hay fields, range lands, or shortly before a crop is harvested (or immediately after a crop is harvested).  The keys to success are timing and seeding method.  The best time to plant is when grains would naturally reseed themselves (usually in the dry or dormant season).  The best way to plant is to disturb the soil as little as possible.  (The more soil is tilled = broken, the more weeds will germinate).  The best methods are to broadcast seed into standing vegetation (pelleted seeds greatly increase seedling survival) or to plant in shallow slits made by a no-till seeder.  Other than planting and harvest, no attention is paid to the crop.  In years with good rainfall, yields are typically 60% to 70% of conventionally grown crops.  In dry years crops are often not worth harvesting for grain (but do produce substantial quantities of forage or surface mulch to protect fields and increase soil organic matter).

Zero input agriculture is the best way to grow small grains where the climate is dry or soils are poor.  The method yields a surprisingly high return on investment because there is little financial risk (only the cost of seeding in a bad year, or the costs of seeding and harvest in a good year).  Because input costs are minimal, profit margins are high.  Thus, zero input agriculture can produce more income than conventional grain farming.

“No-Kill Cropping” is the wave of the future, a convergence of old-school mechanical agronomy with new-school biological agriculture.  The synthesis of these disciplines creates a new way of thinking about farming, an agro-ecological approach where problems are solved by nature rather than by petrochemicals.  Here, the idea is to grow crops and weeds together in mutual symbiosis, rather than spending vast sums to eradicate all competing plant life.

The first time I proposed planting weeds as cover crops, half my audience walked out of the conference room (I think they all worked for Monsanto).

WEEDS AS COVER CROPS:     Weeds make excellent ground covers well worth the cost of seed, fertilizer and irrigation.  Most fields already have sufficient weed populations.  Where land is barren or scraped down to subsoil, broadcast grain elevator screenings liberally.  Elevator screenings are cheap (often free) and contain many weed seeds.

As I write this paper (Monday 1 June 2015) it is almost time to transplant tomatoes in Butler County, Pennsylvania (40.8607 degrees North Latitude, 79.8947 degrees West Longitude).  My fields are a green sea of weeds.  Pigweed (Amaranthus blitum), Lambs Quarters (Chenopodium album), and Common Thistle (Cirsium vulgare) are already 2 to 3 feet high, a respectable nurse crop measuring about 2.5 tons of dry matter per acre.

After lunch I will mow or roll strips through the weeds, overseed each planting strip with Dutch White Clover (Trifolium repens), set 8-inch tall determinate tomato transplants every 4 feet, then run drip irrigation hose down the rows.  Most of the field remains covered by weeds which I leave undisturbed.  I will walk the field once or twice before harvest to rescue the odd tomato plant that gets too crowded by weeds.  A pair of pruning shears quickly dispatches offending vegetation.  The crop gets no other attention until destructive harvest which yields 8 pounds of Number 1 marketable fruit per plant at $0.60 per pound wholesale price for “spray-less tomatoes” (21,000 pounds = 10.5 tons per acre = $12,600 gross income per acre).  That is good money for very little labor and minimal investment (no plowing, staking, fertilizer, herbicides, pesticides, or fungicides).

Lawnmower Farming:     Find the weediest field possible = vigorous growth 5 to 6 feet tall.  Mow widely spaced strips through the weeds.  If possible, run irrigation tape down the rows.  Set transplants then mulch 12 inches deep with cut weeds — this is a form of cold composting known as sheet composting.  Green weeds contain twice the nutrients of fresh dairy cow manure.  Chopped vegetation rots quickly releasing nutrients to feed crops.  Leave remaining weeds standing to provide food and shelter for beneficial insects.  Lawnmower farming does not use land efficiently but it does grow crops cheaply = without tillage, herbicides, fertilizer, or pesticides.

Mow-And-Blow:     On large farms and plantations forage choppers replace common lawnmowers.  Modify delivery chute to deposit chopped vegetation into convenient windrows.  Set transplants and drip irrigation hose down the windrows.  Use mow-and-blow with any kind of vegetation:  Weeds, forage grasses, mulch crops, and mixed species cover crops all do well.  For best results choose plants that produce large yields of biomass = stems and leaves per acre.  If possible, irrigate and fertilize fields to increase mulch yields.

It pays to feed and water weeds.  Weeds use and recycle nutrients efficiently so a little fertilizer creates rampant growth = more biomass for mulch and soil improvement.  For best results apply dilute fertilizer in irrigation water.

>>>     The trick to using weeds as cover crops is to manage them just like any other conventional mulch crop or green manure.  Kill the weed crop by mowing, crimping, or spraying then seed or transplant through the mulch with no-till equipment.  Think of weeds as a mixed cover crop that costs nothing to seed!

>>>     Set aside an acre or two and experiment growing crops in weeds.  The first thing you will discover is that pests do not like weedy fields.  Crops grown in weeds rarely need sprayed.  Fertilizer costs can also be reduced or eliminated because weeds efficiently capture and recycle nutrients.  Water costs also decrease because weeds protect crops from drying winds.

>>>     The only disadvantage to farming weeds is that your neighbors will think you are crazy.  Count your profits and let the naysayers believe as they wish.

Martian Thinking:  “See what the Earthlings are doing, turn 180 degrees in the opposite direction, then work back to what makes sense”.

MARTIAN AGRICULTURE = WEEDS ARE PROFITABLE!     99% of farmers think that weeds are bad.  Eric thinks differently.  I encourage weeds to grow in my fields.  For example:  Why use herbicides in a small grain crop?  Herbicides cost money to apply (and even more money is lost because the crop cannot be sold as “natural” or “organic”).  Modern seed cleaners easily separate weed seeds from crop grains.  Weed seed meal makes ideal organic fertilizer.  (For highest profits sell weed seed meal in 40 pound bags to city gardeners).  Wild oats can be separated from weed seeds and processed into high nutritional value cereal (50% protein rolled oats).  Growing weeds in my grain means that I don’t have to apply insecticides (so I save even more money).  Weeds provide pollen and nectar for bees and other beneficial insects.  Weeds also support primary and alternate hosts for predatory and parasitical insects.  (You need to maintain small populations of “bad” bugs in order to sustain healthy populations of “good” bugs).  Having lots of weeds around helps balance farm ecology (which saves even more money on pest control in other cash crops).  And don’t forget that weeds have extensive root systems that break up plow pans  (compacted soil layers) and increase soil organic matter.  The way Eric looks at this is:  What I lose in grain yield (to weed competition) I gain in lower input costs and higher-margin specialty products.  Even in bad years, Eric always makes more money than his neighbors.  Why?  Because Eric is not looking to win a blue ribbon for maximum yield at the County Fair.  Eric measures success at the bottom line.  He who has more money in his bank account wins!

RELATED PUBLICATIONS:     Trash Farming, No-Till Hungarian Stock Squash, Planting Maize with Living Mulches, Living Mulches for Weed Control, and Crops Among the Weeds.

WOULD YOU LIKE TO KNOW MORE?     Contact the Author directly if you have any questions or need additional information.

Please visit:  — or —  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania 15108, United States of America  — or —  send an e-mail to:  Eric Koperek =

ABOUT THE AUTHOR:     Mr. Koperek is a plant breeder who farms in Pennsylvania during summer and Florida during winter.  (Growing 2 generations each year speeds development of new crop varieties).


What Is It?     Pelleted seeds are enclosed in a layer of fine clay to protect them from insects and birds.  Beneficial micro-organisms, fertilizer, and seed protectants can also be included in the clay pellet as needed.  Pelleted seeds are ideal for no-till agriculture where crops are broadcast seeded into standing vegetation.  Pelleted seeds are also easier to drill or sow by hand because each pellet is large enough to space accurately.

How To Do It:     Use 1 part seeds + 7 parts finely powdered clay = 8 total parts by volume.  (12.5% seeds + 87.5% powdered clay = 100% by volume).  Any kind of sticky clay will work or use dry, powdered clay purchased in 50-pound bags from a pottery supplier.

If preparing clay from scratch, remove and save topsoil then dig clay from subsoil layers.  Wash or sift clay through window screening to remove impurities.  Dry clay then grind before use.  Ideal pelleting clay should be pure and dust-like, similar to wheat flour.

Place seeds in mixing barrel of 5 gallon = 20 liters or larger capacity.  Barrel should not have any paddles, beaters, blades, or other protrusions = inside surface must be smooth and free of all obstructions.  Rotate barrel by hand or machine (like a cement mixer).

Slowly, add fine water mist until seeds are barely damp.

Add dry clay alternately with water mist while revolving barrel continuously.

When pellets are twice the diameter of the seeds continue turning the barrel for 3 to 4 minutes only, just until pellets look glossy.


Gently pour seed pellets onto screens to dry in a well-ventilated place.

Store air dried seed pellets in waterproof containers in a dry place until needed.

Biological No-Till Small Grains:     Broadcast seed pellets by hand or use a rotary spreader.  Sow pellets directly into standing vegetation so that soil remains undisturbed.  (Broken soil stimulates weed germination).

Alternatively, drill pellets using a no-till seeder equipped with sharp coulters and chisel tines or cultivator blades to cut narrow slits in the soil.  (The goal is minimal disturbance of soil surface and plant cover).

Wait patiently until rains come and seeds germinate.

Do not use chemical fertilizers, herbicides, pesticides, or fungicides on fields.  Do not weed by hand nor cultivate by machine.  Control weeds by sowing grain with Dutch White Clover (Trifolium repens) if necessary.  Irrigation is optional, but not essential.

2 to 4 weeks before harvest sow pelletized seed of second crop into standing vegetation of first crop.  This is necessary to control weeds.

When grain is threshed, return all straw and chaff to the field and spread randomly so following crop can grow up through the mulch.

Continue rotating grain crops taking special care to over-seed following crop 2 to 4 weeks before harvesting preceding crop.

This technique works best in climates warm enough to grow 2 grain crops yearly:  A winter grain crop and a summer grain crop.  In cooler climates substitute a short season crop like Buckwheat (Fagopyrum esculentum) or Turnips (Brassica rapa subspecies rapa)  for the summer grain crop. 


Subsistence Grain Farming:     Drill or broadcast seed into standing hay, pasture, range, stubble, or weeds.  For best results sow when grain naturally drops its seeds (most commonly in the Fall = dry or dormant season).  Use pelleted seed if broadcast sowing on soil surface.  Use naked or pelleted seed if planting by drill.  Wait for rain and hope for the best.  In years with good rainfall, subsistence yields will be 60% to 70% of conventionally planted grain crops.  In dry years the crop may not be worth harvesting for grain (but will make forage for cattle).  Even is no crop is harvested, surface vegetation protects land from erosion while roots improve soil structure and fertility.  Subsistence farming makes economic sense because production costs are minimal (seed + 1 pass across the field).  Low costs mean farmers reduce financial risk and gain higher returns on investment.

Seed Bombing:     Seed bombing is a technique used to re-vegetate degraded lands, or to surreptitiously plant vacant lots or other properties not owned by the cultivator = guerrilla gardening.  Seeds are mixed in a stiff clay paste, hand formed into marble to walnut-sized balls, then air dried and stored until planting.  The clay balls are randomly broadcast = bombed over the landscape (or discretely dropped where soil and micro-climate appear most favorable).  A planting density of 10 balls per square meter or yard is typically used for land reclamation projects.

How To Make Seed Balls:     Seed balls are much larger than pellets.  Typical seed balls are the size of large marbles or ball bearings and contain approximately 1/2 fluid ounce = 1 Tablespoon = 3 teaspoons = 15 milliliters = 15 cubic centimeters of clay.  Very large seed balls can be double this size = 1/4 cup or approximately the volume of a walnut in its shell.  Use the following recipe to make seed balls for land restoration projects:

1 part seeds + 3 parts finely sifted compost + 5 parts clay + 1 to 2 parts water = 9 to 10 total parts by volume.  Compost is necessary to provide symbiotic fungi essential for root growth.   Mix compost with 10% organic seed protectant (powdered chili pepper) if desired.  1 part organic fertilizer (phosphate rock or bone meal) can be substituted for an equal volume of clay powder to help establish seedlings in phosphorous deficient soils.  Other additives might include nitrogen-fixing bacteria or fritted trace elements, as needed.

Combine in order seeds, compost, clay, and water.  Mix gently until paste has uniform consistency like bread dough.  Portion paste with cookie scoops then shape balls by rolling clay between palms of hands.  Place tightly formed (crack free) balls in a single layer on screens to air dry in the sun.  Store bone-dry seed balls in a moisture-free, well ventilated place until ready to plant.

Carefully encase large seeds like maize, sunflower, peas, beans, lentils, pumpkins, squash, gourds, cucumbers, and melons in individual seed balls.  Mix all small seeded crops (including grasses, clovers, weeds, and wildflowers) randomly with the clay paste.

For land restoration projects choose seed mixtures carefully:  Best results are obtained by combining seeds of native plants that normally grow together in the wild.  It is good practice to include a wide range of species:  Cool and warm season plants, annuals and perennials, grasses, wildflowers, broadleaf plants, weeds, clovers and other legumes.  If budgets are tight or seed too expensive, obtain weed seeds from local grain elevators.  Elevator screenings are free or cheap and contain large amounts of weed seed.  Weeds are ideal species for colonizing bare soils.  Weeds heal the earth allowing less hardy species to become established.

Would You Like To Know More?     Please contact the Author directly if you have any questions or need additional information about pelleted seeds for agriculture and land reclamation.

Please visit:  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United Sates of America  — or —  send an e-mail to:  Eric Koperek =

About The Author:     Mr. Koperek is a plant breeder who farms in Pennsylvania during the summer and in Florida during the winter.  (Growing two generations yearly speeds development of new crop varieties).


Long before there were herbicides, diesel tractors, or rotary cultivators, smart farmers learned to manage their weeds.  How did they do it?  Here’s how:

Living mulches suppress weeds, reduce soil erosion, enhance soil fertility, attract beneficial insects, and help retain soil moisture.  The best living mulches are low-growing, nitrogen fixing legumes.  Dutch White Clover (Trifolium repens) is a good example.

Before seeding clover or any other living mulch, remember that two crops are growing on the same land at the same time — the mulch crop and a cash crop.  Success requires careful management or both crops may fail.

All living mulches compete with their companion crops.  The extent of competition and consequential yield loss vary with management and crop type.  For example, under drought conditions shallow rooted crops generally show more yield loss than deep rooted crops.  Low or slow growing crops may be overwhelmed by more aggressive companion crops.

As a general rule, living mulches are not recommended where drought is expected because yield losses are too high.  However, many crops benefit from clover mulches during dry conditions — the clover shades the soil, retards evaporation, and increases humidity around the cash crop.

Transplanting Vegetables into Clover

Dutch white clover makes good living mulch for TRANSPLANTED vegetable crops provided:  (1)  Crops are irrigated,  (2)  Crops are fertilized, and  (3)  Crops are protected for the first 4 to 6 weeks from competition by the clover.

1 to 2 inches of water are needed weekly to grow both clover and vegetables without undue competition for moisture.  If water is limiting, it is best to drip irrigate the cash crop rather than water the entire field.

Nitrogen fertilizer is not often required for small grains but is recommended for maize, fruits and vegetables.  The reason is that clover fixes about 100 pounds of nitrogen per acre but these nutrients are not immediately available — they are retained by the living mulch.  Phosphorous and potassium should be applied according to crop requirements along with lime to correct soil acidity.  Dutch white clover needs sulfur and responds well to powdered agricultural gypsum at 2 to 3 tons per acre.

Dutch white clover grows only 6 to 8 inches high so there is little competition for light except when crops are young.  Mow a narrow strip where transplants will be set, or apply a circle of mulch around transplants to give crops a head start.  Once crops are established they will overgrow the clover and produce normal harvests.

Aggressive, fast-growing crops like tomatoes, peppers, okra, melons, squash, sweet potatoes, gourds & pumpkins all do exceptionally well when transplanted into Dutch white clover.  Cucumbers are slower growing and require extra mulch to protect them from early season competition with the clover cover crop.

Stake-less = self-supporting tomato varieties (with thick upright stems) grow well in Dutch white clover.  The living mulch keeps fruits clean and allows easy harvest even in rain-soaked fields.

Once established, Dutch white clover is an aggressive mulch crop that blots out most weeds.  Walk the fields and hand pull any weeds that escape the clover.  Alternatively, thin weeds to at least 1 yard or 1 meter apart.  Thinly spaced weeds will not significantly affect quality or yields of cash crops (but will provide food and shelter for beneficial insects).  Weedy fields often require little or no insecticides to control crop pests.

Direct Seeding into Standing Clover

Dutch white clover is not well suited to direct-seeded crops, especially those with small seeds or slow germination.

Common potatoes are an exception, especially if whole tubers are planted to establish the crop.  Roto-till a narrow strip just wide enough to get the seed potatoes in the ground.  After planting, over seed tilled rows with additional clover seed to maintain soil coverage.  The potatoes grow through the clover without trouble.  Fall potatoes (planted after hard frost in November) averaged 22.8 tons per acre when grown in irrigated Dutch white clover.  Adjacent non-irrigated fields averaged 16.4 tons per acre, the yield loss due to water competition.

Costa Rican Indians grow dry beans by broadcasting seed into the weediest fields available.  The weeds are then hand cut and left as mulch to protect the germinating beans.  Yields are low, only 400 to 500 pounds per acre, but there are no costs other than labor for planting and harvesting.

The same technique works with Dutch white clover.  Spring turnips broadcast into standing clover averaged 10.8 tons per acre when the clover was intensively grazed for 3 days and the seed stomped into the soil by sheep.  Adjacent plots mowed 1-inch high averaged 14.3 tons per acre.  Control plots (no grazing or mowing) averaged only 0.90 tons per acre because of intense competition from the clover.  In comparison, winter turnips (sown after the first snow) averaged 13.1 tons per acre.

These results demonstrate the importance of timing when sowing any small-seeded crop into Dutch white clover.  Ideally, seed should be sown when the clover is dormant.  The next best choice is “sow and mow” (or sow and graze).

Direct seeding into standing clover is not recommended unless the clover is knocked back to reduce competition with the primary crop.

In non-irrigated, non-fertilized fields, flint corn transplanted on 40 inch centers into mown Dutch white clover averaged 68 bushels per acre (along with 1,300 pounds of dried beans and 9,600 pounds of pumpkins).  Adjacent fields transplanted into Red Clover (Trifolium pratense) were overwhelmed and failed to make a crop.

Careful timing is essential when planting mixed crops into living mulches or bare soil.  For example, in a maize-bean-pumpkin polyculture, the primary maize crop should be at least 18 inches high (4 to 8 leaves) before beans or pumpkins are sown, otherwise the grain will be smothered by the companion crops.

Strip cropping combines the pest control advantages of polycultures with the high efficiency of mechanized agriculture.  For example, fields seeded into mown Dutch white clover with 4-row strips of maize alternated with equal width strips of dry beans and winter squash (maize-beans-maize-squash, et cetera) out yielded individual crops grown as monocultures.  The yield advantage for maize alone averages 15% when grown in narrow 4-row strips with other companion crops.  Yield increases from strip-cropping are attributed to better light penetration into the maize canopy, and reduced pest populations in the beans and squash.

Living mulches work especially well with intensive horticulture systems like truck farms and market gardens where careful management and judicious cultivation (including mulching and mowing) prevent the companion crops from overgrowing the cash crops.  When crops are planted into living mulches, entire farms (up to 25 acres) can be run with only a small rear tined roto-tiller and common lawn mower.  Leaving strips of hay, wildflowers, and clover between cash crops and around field borders creates a sanctuary for beneficial predatory insects that help keep pest populations under control.

Seeding Small Grains into Clover

Seeding small grains into living mulches works best when:  (1)  The companion crop is dormant or its growth retarded by mowing, grazing, or rolling, and  (2)  The grain crop is selected for a competitive growth habit.  Heirloom (non-dwarf) varieties usually pair well with understory legumes like Dutch white clover.  Alternatively, clover can be broadcast into standing grain that is well established (8 to 12 inches high).  Again, careful timing is essential to prevent the cover crop from overwhelming the cash grain.

In non-irrigated, non-fertilized fields, fall seeded wheat averaged 28.1 bushels per acre when broadcast into dormant clover.  Spring seeded wheat averaged 21.6 bushels per acre when the crop was “frost seeded” (planted in frozen soil).  Late spring “sow & mow” wheat averaged 19.9 bushels per acre while wheat broadcast into standing clover barely made a crop, only 3.4 bushels per acre.  In comparison, broadcast planted spring wheat top-seeded with clover when the wheat was 8 inches high averaged 15.4 bushels per acre.  To put these yields in perspective, conventionally drilled & cultivated spring wheat (without clover) averaged 39.7 bushels per acre (without irrigation) and 78.5 bushels per acre (with irrigation).

Extra water and fertilizer reduces competition for moisture and nutrients resulting in higher yields.  In irrigated, fertilized fields, fall seeded wheat averaged 70.4 bushels per acre when broadcast into dormant clover.  Frost seeded spring wheat averaged 56.5 bushels per acre, while late spring (sow & mow) wheat averaged 61.9 bushels per acre.  Spring wheat broadcast into standing clover failed to make a crop, while clover sown into standing 12 inch high wheat averaged 74.7 bushels per acre.

Sometimes Old Ways are Best

The clover-wheat-turnips rotation common during the Renaissance is a good example of how cover crops and living mulches can be integrated with modern low-till and no-till agriculture.  Typically, the clover cover crop was “hogged down” (uprooted by foraging pigs); this eliminated the need to plow and harrow.  Wheat was then broadcast by hand and the seed trod into the ground by sheep or cattle.  Turnips were broadcast into the wheat as the heads were filling out, and clover was broadcast over the turnips a few weeks before harvest.  This rotation reliably averages 40 bushels of wheat per acre under European weather conditions without the need for irrigation, synthetic fertilizer, machinery, fossil fuels, or agrochemicals.  (Favorable rain or irrigation boosts this average to 80 bushels per acre).  Low production costs more than compensate for modest yields, a primary consideration for most farmers operating on slim profit margins.

Thoughtful Weed Management

The key point to intelligent weed control is to disturb the soil as little as possible, just enough to get a crop into the ground.

Remember that weeds have evolved specifically to rapidly colonize bare soil.  The more soil is tilled, the more weeds are stimulated to grow.  Conventional bare earth agriculture invites weed invasions.  In order for crops to coexist with weeds and living mulches, a different approach is needed.  Ideally, crops should be over seeded or transplanted with the minimum possible disruption to both soil and surface vegetation.  Often, specialized equipment is needed.  For example:  Why dig a long furrow when only a few discrete holes are needed for seeding?

Without irrigation and fertilization, competition between living mulches and cash crops can reduce yields 50% or more.  Poor judgment (such as seeding at the wrong time) can result in crop failure.

Clearly, there is significant competition from living mulches; the question is whether the savings from reduced tillage and other costs are outweighed by observed yield reductions.  These differences may not be significant depending on how the crops are marketed.  For example, the premium for “organic” produce and the profits from artisan breads are substantial.  In this case, lower yields are offset by higher margins from specialty products sold to niche markets.

Agronomy Notes

>>>  Dutch white clover and winter wheat can be seeded at the same time.  Remember to plant only after the Hessian Fly Date for your area.  This technique works well with all winter grains.

>>>  Top seeding Dutch white clover usually requires a separation of 7 to 14 days between plantings (about the time it takes for the cash crop to germinate).  Slower growing crops need more time to become established.  For example, sweet corn should be at least 6 inches tall before over seeding with Dutch white clover.  Rule-of-Thumb:  Maize should have 4 to 8 leaves (16 to 24 inches tall) before top seeding with Red Clover (Trifolium pratense) or any other type of tall growing clover.

>>>  Organic herbicide may be used instead of mowing, grazing or cultivation to control Dutch white clover prior to planting a cash crop.  For example, a narrow strip of clover can be killed with herbicide before transplanting vegetables.  Use spray shields to prevent herbicide drift.  It is important to disturb as little of the living mulch as possible — kill just enough clover to get the crop established.  Removing too much plant cover favors weed growth.

>>>  If clover seed is unavailable or too expensive, use weeds as living mulch.  This technique works best with fast growing vine crops.  For example:  Choose the weediest field available then transplant melon seedlings on 10 to 12 foot centers.  Mulch each transplant liberally with straw or any other convenient material.  Mulch is necessary to keep weeds at bay only until vines begin to run.  Once started, vines will overgrow the nurse crop.  Melons thrive in the light shade of weedy fields.  As an added benefit, vines growing among weeds rarely have insect problems.

>>>  Red Clover (Trifolium pratense) seed is usually less expensive than Dutch white clover (Trifolium repens).  Sweet corn, popcorn, flint corn, flour corn, pod corn, and dent corns all grow well when planted with red clover.  Top seed = over seed maize with red clover at the last cultivation or when plants have 4 to 8 leaves.  The corn plants are tall enough (about 1 1/2 to 2 feet high) so that competition with the living mulch is minimal.

>>>  Any type of maize can be seeded directly into standing red clover using a no-till planter with a fluted coulter.  Two weeks later the field should be closely mowed with a swathing board and divider to keep the clover from falling on the planted rows of corn.  Alternatively, clover can be mowed directly before seeding.  Watch regrowth carefully; a second mowing may be required 2 weeks later.  No herbicides are needed if maize is planted into standing clover; nitrogen fertilizer is not required if clover has grown on the land for 1 or more years.

>>>  Maize is sensitive to drought, especially during pollination and when ears are filling out.  For highest yields apply 1 to 2 inches of water weekly to prevent moisture competition between crop and living mulch.

>>>  Planting hybrid sweet corn into standing red clover yields about 415 sacks per acre on average when sweet corn is seeded 8 inches apart within rows and 30 inches between rows = 25,979 seeds per acre.  Actual plants per acre is approximately 21,000 (17% field loss rate is common).  1 sack = 52 ears = 4 baker’s dozen = 21,580 marketable ears per acre.  Note:  Yield figures are discounted 50% for typical losses to crows, deer, groundhogs, coons, earworms, undersize or poorly pollinated ears, and other causes.

>>>  It is best to use pelleted seed when hand dropping or broadcast seeding into living mulches.  This is especially true for large-seeded crops like peas, beans, maize, melons, and squash.  Pelleted seeds greatly increase germination and stand establishment rates.

>>>  Seedling survival and stand establishment are optimal when planting is done with no-till equipment.  Expect 20% to 25% loss rates when broadcasting naked, unprotected seed into living mulches or other standing vegetation such as hay or weeds.

>>>  Biological agriculture is all about managing little details, for example, choice of companion crop:  Flour corn top seeded with sweet clover (Meliotus officinalis) was overwhelmed and failed to make a crop.  Flour corn planted with standard (tall) red clover yielded 37.4 bushels per acre.  Flour corn planted with medium red clover yielded 41.8 bushels per acre.  Flour corn planted with Dutch white clover yielded 47.6 bushels per acre.  Yield differences were entirely due to living mulch height.  Taller clovers compete more strongly with maize cash crops, especially when corn plants are young.

>>>  Every farm has different soil and micro-climate.  Agronomic practices that work in one field may fail in another.  For best results, every farmer should maintain one or more research plots so that new methods can be tested and adapted to local conditions.

 For More Information

Readers who have any questions or require additional information about living mulches should contact the Author directly:

Please visit:  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or — send an e-mail to:   Eric Koperek =

Most agricultural universities publish extensive literature on cover crops, nurse crops, living mulches, green manures, and crop rotation.  Contact your County agricultural extension agent or search the Internet for relevant publications.

About the Author

Mr. Koperek is a plant breeder who farms in Pennsylvania during the summer and Florida during the winter.  (Growing 2 generations per year speeds development of new crop varieties).


2012 Organic Cabbage Trial

This is a demonstration project:  A single field without controls or replications for statistical analysis.  The purpose of this trial is to explore possibilities before launching a full-scale research program.

Experimental Location:  Homestead, Florida, United States of America.  25.47 degrees North Latitude, 80.52 degrees West Longitude.

Climate:  Homestead has a semi-tropical monsoon climate with a hot, humid summer and a cooler, drier winter.  Average annual temperature = 74.8 degrees Fahrenheit = 23.75 degrees Centigrade.  Average annual rainfall = 58.23 inches = 147.90 centimeters.  Average January low temperature = 56 degrees Fahrenheit = 13.2 degrees Centigrade.  Average January high temperature = 77 degrees Fahrenheit = 24.8 degrees Centigrade.  Frost Free Growing Season = approximately 355 days.  Homestead gets about 5 to 10 frosts (36 degrees Fahrenheit) and freezes (32 degrees Fahrenheit) each winter.

Experimental Plot Size:  1 acre = 208 feet x 208 feet (approximately).

Soil Type:  Everglades Peat = Muck

Crop Rotation:  Sunn Hemp (Crotalaria juncea) was planted in spring 2012 to suppress weeds and control root knot nematodes.  Hemp cover crop was shredded with a forage chopper then Crimson Clover (Trifolium incarnatum) was broadcast seeded over hemp mulched field.  Cabbage seedlings were transplanted into rotary mowed crimson clover in November 2012.

Tillage:  Field was mulched using a common silage chopper.  Crimson clover was cut with a rotary mower.  Cabbage seedlings were planted using a no-till transplanter with a fluted coulter.

Plants Per Acre:  Cabbage transplants were set 18 inches apart in rows 30 inches apart = approximately 11,000 plants per acre.  (138 plants per row x 83 rows per acre = 11,454 plants per acre exactly).  80% field survival is common so final plant density = approximately 9,000 plants per acre.

Crop Variety:  Brassica oleracea cultivated variety “Golden Acre”.  This is an early season (58 day) round cabbage with small heads averaging 3 to 4 pounds each.

Common Weed Varieties:  Bull Thistle (Cirsium vulgare), Coffee Senna (Senna occidentalis), Hemp Sesbania (Sesbania exaltata), Morning Glory (Ipomoea species), Lambs Quarters (Chenopodium album), and Pigweed (Amaranthus blitum).

Weed Management:  Sunn hemp cover crop and crimson clover living mulch eliminated most weeds.  Field was better than 95% weed free so no herbicides were used for this trial.

Weed Spacing:  Approximately 2,200 weeds grew above the crimson clover living mulch = approximately 1 weed per 19.8 square feet.  Clumps of weeds were hand thinned to single weeds spaced about 4 to 5 feet apart.

Irrigation:  Overhead sprinkler irrigation, 1 to 2 inches applied each week as needed.

Organic Fertilizers:  Greensand and colloidal phosphate rock were broadcast with sunn hemp seed according to soil test recommendations.  Hemp seed was covered with 20 tons = 40,000 pounds of composted stable bedding.  Fish emulsion and liquid seaweed (Kelp) were used as starter fertilizers for cabbage transplants.

Insect Control:  Cabbage plants were sprayed with a harmless biological insecticide “BT” = Bacillus thuringiensis subspecies kurstaki strain SA-12 every 7 to 10 days throughout the growing season.  BT is a naturally occurring bacterial disease that kills caterpillars = juvenile forms of moths and butterflies.

Cabbage Yield:  Approximately 9,000 marketable heads were harvested.  Average head weight = approximately 3.375 pounds = 3 pounds 6 ounces (normal range is 3 to 4 pounds).  Yield per acre = approximately 30,000 pounds = 15 tons.

Production Costs:  $5,924 per acre (mostly for amortized irrigation system and farm machinery).

Cabbage Income:  30,000 pounds cabbage (9,000 marketable heads) x $0.35 per pound organic produce premium wholesale price = $10,500 gross income.

Net Income:  $10,500 gross income – $5,924 production costs = $4,576 net income from 1 acre of organic cabbage sold wholesale.  ($4,576 net income / $10,500 gross income) x 100 = 43.58% before tax profit.  ($4,576 net income / $5,924 production cost) x 100 = 77.2451 = 77% gross return on investment.

Agronomy Notes:

>>>  Most south Florida soils are coarse sands with very low humus content (often less than 2%).  Large amounts of organic matter must be added to these soils to keep them productive.  Cash crops must be rotated with soil building cover crops in order to maintain humus levels at 3% or above.

>>>  Muck soils also require large amounts of organic matter to replace humus lost to accelerated decomposition when swamps are drained.  Drainage and cultivation expose peat soils to large amounts of oxygen.  Rapid oxidation causes soil subsidence if organic matter is not replaced.

>>>  Root knot nematodes are serious agricultural pests in south Florida.  The most economical control method is to rotate cash crops with highly nematode-resistant cover crops like Sunn Hemp (Crotalaria juncea), Velvet Bean (Mucuna deeringiana), Cowpea (Vigna unguiculata), or Hairy Indigo (Indigofera hirsuta).

>>>  Sunn hemp, forage maize, and silage corn produce enormous amounts of organic matter for soil improvement (surface mulch or green manure).  Few farmers use hemp or maize as green manure or mulch crops because the plants must first be shredded in order to decompose quickly.  (If long-lasting mulch is desired, knock down cover crops with a roller-crimper then plant through dead mulch with a no-till seeder or transplanter).

>>>  Widely spaced weeds did not appear to have any negative effects on cabbage yield or quality.  Many cabbages growing near weeds were larger than those without any weed competition.  Light shade may be beneficial for cabbage growth.

>>>  Crimson Clover (Trifolium incarnatum) is often sown along Florida highways because it has large flowers.  Crimson clover makes good living mulch because it normally grows only 6 to 12 inches high.  Ideal living mulches grow short so they do not compete with crop plants for light.

Would You Like To Know More?  Please contact the Author directly if you have any questions or need additional information about using living mulches for weed control.

Please visit:  — or —  send your questions to:  Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or —  send an e-mail to:  Eric Koperek =

About the Author:  Mr. Koperek is a plant breeder who farms in Pennsylvania during the summer and Florida during the winter.  (Growing 2 generations each year greatly speeds development of new crop varieties).