As I sit here at my drafting table, the local code enforcement officer is looking askance at my “lawn” which is not mowed at the regulation height of 6 inches or less. Instead, I have 2 research plots in front of my office, both planted with Peruvian land race potatoes. One plot is mulched with stable bedding, the other plot covered with weeds up to 4 feet high. The mulched potatoes are riddled with flea beetles; there are so many holes that the leaves look like window screening. 3 feet away, potatoes growing in weeds have only a few scattered holes in their leaves. These results are typical of crops grown au naturel = in the wild.
When I was young, “good” farmers were judged by the straightness of their furrows and the cleanliness of their fields. Bare earth and weed-free crops were the standard of good agricultural practice at that time. Contrarian that I am, my fields were always less than pristine. Many decades later, my crops are still a herbicide salesman’s nightmare. The reason is that I have long since stopped trying to eradicate weeds. Now, I manage them. I encourage them. I even plant weeds because I never seem to have enough wild plants in my fields.
Am I daft? Certainly. I am also wealthy because I don’t have big pesticide bills to pay. My crops may not make record yields, but I am not aiming for a blue ribbon at the County Fair. I measure success on the bottom line. Who wants to spend $2,000 to plant a half acre of peppers? I gladly trade low production costs over huge input bills. I make more money by saving money. As an added benefit, my customers can pick vegetables without worrying about being poisoned by agricultural chemicals. I don’t need “organic” certification. My customers pay me not to spray. That’s good business any way you figure it.
Down the road I have a wilderness of citrus interspersed with live oaks, Spanish moss, and pangola grass. It’s an old orchard that is long overdue for rotation, but it still makes me money because I spend almost nothing to maintain the trees. Every now and then I spread some racetrack manure. The irrigation system turns itself on and off. The weeds grow 6 feet high. Once a year, right before harvest, I mow between the trees — just enough so folks can pick the fruit. Result: No bugs on my trees. Across the hedgerow of old-fashioned hibiscus, my neighbor clean cultivates his orchard and sprays with robotic frequency. Every spider mite in the district comes to eat his leaves. Chemical companies use his orchard to test new pesticides. The mites don’t seem to mind; they eat insecticide like salad dressing.
Up the road are stake-less tomatoes (with thick, upright stems) transplanted into Berseem = Egyptian clover (Trifolium alexandrinum). I used to walk the fields pulling any weed not blotted out by the clover. Now, I don’t bother. I let the weeds grow wild. Occasionally, I thin the weeds if they grow too thick. My fields look messy but I rarely see a hornworm.
Across the lane is my pride and joy: A jungle of weeds and melons. The weeds grow over my head and the melons grow over the weeds. The trick is to mulch the young melons (or mow the weeds) just until the vines start to run. After the melons are well established, the crop fends for itself. Vine crops thrive in the light shade cast by nearby weeds; the best fruits come from the weediest parts of the field. Insect pests don’t like the broadleaf jungle so I never have to spray vine crops grown in weeds.
Intelligent Weed Management
Tired of getting sick every time you spray a field? Use the following rules-of-thumb to create a healthy cropping system tailored to your local soil and climate:
>>> Weeds are a type of living mulch: Plants grown to reduce soil erosion, enhance soil fertility, attract beneficial insects, and help retain soil moisture. Before planting into weeds 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 many 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 living mulches during dry conditions — the companion plants shade the soil, retard evaporation, and increase humidity.
>>> Weeds make good living mulches 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 weeds.
>>> 1 to 2 inches of water are needed weekly to grow both weeds 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.
>>> Weeds grow quickly so there is often intense competition for light when cash crops are young. Mow or roll 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 well established they will usually hold their own. If necessary, prune or thin weeds to increase light penetration for cash crops.
>>> Roller-crimpers are better than mowers for weed management. Mowing stimulates plant regrowth; crimping does not.
>>> Aggressive, fast-growing crops like tomatoes, peppers, okra, melons, squash, sweet potatoes, gourds and pumpkins all do exceptionally well when transplanted into weeds. Cucumbers are slower growing and require extra mulch to protect them from early season competition with weedy nurse crops.
>>> As a general rule, broadleaf weeds make better nurse crops than wild grasses which are more competitive and difficult to manage. Where weedy grasses are a problem, burn the fields or treat with organic herbicide before transplanting cash crops.
>>> It is good practice to leave strips of meadow, weeds, wildflowers, cover crops, or other living vegetation between or around fields of cash crops. These buffer strips act as refuges for beneficial insects needed to control crop pests. The best refuge plants have small flowers so that good bugs can easily obtain pollen and nectar. Examples include buckwheat, turnip, rape, clover, and any member of the botanical family Apiaceae = Umbelliferae = carrot family = Anise, Dill, Angelica, Chervil, Celery, Caraway, Coriander, Cumin, Carrot, Fennel, Lovage, Parsnip, and Parsley.
>>> As a general rule, it is unwise to harvest fields all at once. Divide fields into strips or parcels then harvest each sequentially. Leaving un-harvested areas allows predatory insects to migrate from disturbed spaces. The idea is to preserve a balance between predator and prey to prevent sudden population crashes. Translation: You want a resident population of good bugs waiting to eat any bad bugs that fly into your fields.
>>> If weedy fields are unavailable for planting, seed conventional cover crops. The best living mulches are low-growing, nitrogen fixing legumes like Dutch White Clover (Trifolium repens), Crimson Clover (Trifolium incarnatum), and Red Clover (Trifolium pratense). Remember to inoculate legume seeds with compatible nitrogen-fixing rhizobium bacteria.
>>> Where land is weak or vegetation sparse, plant weeds to restore soil health. Spread weedy hay over sick fields. Seed wildflowers adapted to your local climate. Broadcast grain elevator screenings liberally; screenings are dirt cheap (often free) and contain many weed seeds. If necessary, seed a nurse crop of common rye (Secale cereale) or millet (Panicum miliaceum) to help establish a vigorous weed population.
>>> Where agriculture is problematic (bare soils, unfavorable climate, no water or fertilizer) it is best to seed mixed cover crops to mimic the diversity of naturally weedy fields. Choose 2 cool season grasses + 2 cool season broadleaf plants + 2 cool season legumes + 2 warm season grasses + 2 warm season broadleaf plants + 2 warm season legumes. Include 2 root crops (forage radish, turnip, or stock beet) to help break up compacted soil layers. Total: 14 different cover crop species. Plant at least 20 pounds of mixed cover crop seed per acre = 23 kilograms per hectare.
>>> Weeds are nature’s band-aid; they are specifically evolved to rapidly cover disturbed soils. Tillage encourages weed germination and stimulates weed growth. Consequently, to manage weed populations avoid tillage whenever practical.
>>> It is best not to disturb healthy populations of weeds or cover crops once they are well established. Broadcast, transplant, or drill cash crops into surface vegetation. Use equipment specifically designed for no-till planting on trashy, high-residue fields. For surface (broadcast) planting, increase seeding rates to maximum levels or use clay pelletized seed. (Pelleted seeds greatly increase plant survival).
>>> Weeds are most efficiently controlled by using the natural competitive abilities of crop plants. For example, top seed forage radish (Raphaus sativus variety longipinnatus) over oats when they start to head out. The radish understory crop grows slowly until grain harvest. After oats are combined, radish growth explodes quickly covering the field and blotting out nearly all competing plants. Weeds never have a chance to get established. Top seeding into standing vegetation is a great way to grow small-seeded crops without using herbicides.
>>> Grind weed seeds into flour and use like cotton seed meal as a cheap, slow-release organic fertilizer. 1 ton of weed seed meal supplies approximately 54 pounds of nitrogen, 18 pounds of phosphorous, and 18 pounds of potassium (2.7% nitrogen, 0.9% phosphorous, and 0.9% potassium by weight). Note: There is no standard analysis for weed seed meal. NPK values vary depending on the mixture of species in local samples.
>>> 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.
>>> Effective weed management requires careful observation and close attention to detail. Every farmer must become a weed biologist. Timing of field operations is critically important. Planting 2 weeks earlier or later can result in stunning success or dismal failure. Continuous experimentation is needed to develop weed control programs for each individual crop, field, and farm.
Organic No-Till Weed Control
Conventional no-till agriculture relies on synthetic herbicides to control weeds. Following no-till method uses an all-natural herbicide substitute made from acetic acid (vinegar) and citric acid (lemon juice). Combination makes a non-selective vegicide that works like Roundup (glyphosate) to kill both grasses and broadleaf weeds.
Organic Herbicide Formula By Weight For Farming
10% Glacial Acetic Acid (liquid) 100 grams
5% Citric Acid (powder) 50 grams
83% Water 830 grams
2% Wetting Agent (surfactant) 20 grams
100% TOTAL PARTS BY WEIGHT 1,000 grams
This is a non-selective herbicide = kills everything. Wetting agent is essential for herbicide to stick to leaves. For best results, apply herbicide on a warm, sunny day when weed leaves are dry. Herbicide works best on annual broadleaf weeds and grasses 6 inches or less in height. This is a burn down herbicide; only surface vegetation is killed. Herbicide will not kill perennial weeds with deep taproots or grasses with growing points below soil surface. Herbicide is not translocated to roots or other plant parts. Weeds die from water loss through their leaves. Caution: Glacial acetic acid (industrial strength vinegar) is strongly corrosive. Protect skin and eyes from acid. Wear gloves and goggles when mixing and spraying herbicide. Rinse with pure water if necessary.
Organic Herbicide Formula By Volume For Gardening
This formula uses common vinegar (5% acetic acid) and bottled lemon juice (3% to 8% citric acid) that can be purchased from neighborhood grocery stores.
1,250 milliliters Common White Vinegar 5 Cups
250 milliliters Bottled Lemon Juice 1 Cup
30 milliliters Dish Washing Detergent 2 Tablespoons
1,530 milliliters TOTAL VOLUME 6 1/8 Cups
Above concentration will kill annual broadleaf weeds and grasses 6 inches or less in height. For best results apply herbicide on a warm, sunny day when weed leaves are dry.
Organic No-Till Procedure
This technique works best with small grains, turnips, and other crops that can be broadcast rather than drilled.
(1) Select ground with good weed or crop cover. Weeds or nurse crop will be used as mulch to protect germinating cash crop. (2) Broadcast seed into standing weeds or cover crop. (3) Kill weeds or nurse crop with organic herbicide. (4) Mow weeds or nurse crop when dead. (5) If desired, top seed established crop plants with Dutch White Clover (Trifolium repens), Red Clover (Trifolium pratense), Crimson Clover (Trifolium pratense), or other low growing legume.
>>> 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, crimping, or spraying with herbicide. Seeds or transplants are then set through the surface mulch.
>>> 8,000 to 10,000 pounds of straw mulch per acre are needed to achieve 90% weed control. A crop of rye grain (Secale cereale) 5 to 6 feet high normally yields 4 to 5 tons of biomass per acre. Most mulch-in-place systems use grass crops because cereal straw decomposes slowly. Broadleaf cover crops rot faster leaving holes in the mulch through which weeds grow.
>>> Mowed fields are best transplanted by hand because no-till planters often get clogged by loose plant materials. Sickle-bar mowers are better than rotary or flail mowers because they do not chop or scatter the mulch. Good weed control requires a dense layer of long straw which blocks sunlight and acts as a physical barrier to weed emergence.
>>> Rolling down a cover crop is faster than mowing. Roller-crimpers are cheaper than mowers and cost less to operate.
>>> Roller-crimped fields are ideal for no-till seeders and transplanters. Always work “with the grain” = in the same direction as the cover crop or weeds are rolled. Never work against or across the grain or surface mulch will clog planting machinery.
>>> Mulch crops are best killed when in full flower or early seed set. Earlier harvest reduces mulch yields and increases chances of regrowth. (You do not want the cover crop competing with the cash crop). Late harvest risks reseeding by the mulch crop. (Seed carryover between seasons turns a good mulch crop into a bad weed problem). For example: The best time to kill cereal rye is when the seeds are in their milk or soft dough stage. Harvest at this time guarantees maximum straw yield and zero regrowth.
>>> It is good practice to top seed a low growing legume like Dutch White Clover (Trifolium repens) immediately after seeding or transplanting cash crops. Clover plants fill any holes in the mulch and increase biodiversity in the field.
>>> To make your own roller-crimper, start with a steel cylinder 12 to 24 inches diameter, like a lawn roller. The cylinder can be any convenient length; 8 to 10 feet long is the smallest roller recommended for efficient commercial farming. Weld dull blades of 1/4 inch steel to the roller. Each blade should be 4 to 5 inches high. Space blades 7 to 8 inches apart. Angle blades across the cylinder in a wide V-shape like a chevron; this prevents roller from bouncing around and greatly improves crimping effectiveness. Mount roller on frame attaching to a 3-point hydraulic hitch on tractor front. When finished, roller and frame should weigh 3,000 pounds; this weight is necessary to thoroughly crimp mulch plants so they do not regrow. If desired, roller can be designed to hold water ballast so that weight can be increased for tough-stalked mulch crops like forage maize. Detailed plans for roller-crimpers are available from the Rodale Institute = http://www.rodaleinstitute.org
Plowing in the Middle Ages was hard, slow work. Heavy wood plows were ponderous, inefficient, and difficult to turn. A man with a team of 2 oxen took 3 whole days to plow and harrow a small 1-acre field just 22 yards wide x 220 yards long. The alternative was even worse: Digging by hand was back-breaking labor requiring at least 30 days to till 1 acre with spade or fork. It did not take long for farmers to figure out easier ways to grow crops. The Dutch were the first to apply the new agricultural technology which married free-range pig ranching with a clover-wheat-turnips rotation:
In spring, fence off plot of Dutch White Clover (Trifolium repens) and turn in swine. (Pigs like Dutch clover because it is sweet. Do not put rings in hogs’ snouts or they will not be able to root). Pigs “plow” soil like a rototiller, uprooting all vegetation. Broadcast spring wheat onto pig-tilled earth then drive sheep back and forth across land. Sheep stomp wheat seeds into ground. When wheat starts heading out (or at least 2 weeks before harvest) broadcast turnip seed over standing grain. After wheat is cut, fast-growing turnip leaves carpet field overwhelming competing plants. About 2 weeks before turnip harvest broadcast clover seed over standing foliage. When roots are lifted, young clover plants blanket field, blotting out most weeds. Clover cover crop protects and fertilizes soil until following spring when rotation cycle is repeated.
On a typical farm in northern France or upstate New York, no-till clover-wheat-turnips reliably yields 40 bushels of wheat per acre (2,400 pounds per acre = 2,694 kilograms per hectare) without hybrid varieties, irrigation, tractors, diesel fuel, chemical fertilizers, synthetic herbicides, insecticides or fungicides. (Note: This rotation works equally well with Oats = Avena sativa, Barley = Hordeum vulgare, Rye = Secale cereale, or Millet = Panicum miliaceum).
No-Till agronomy is not a new idea; no-till was practiced in the Middle Ages (and probably earlier). Then, no-till was used mostly by small farmers who did not own draft animals — or — as an emergency measure practiced only when primary crops failed or when an army swept through the district (stealing all of the food and farm animals). Medieval records indicate that no-till was a desperation technology often used by peasants to prevent starvation:
Foul weather prevailed through spring. Fields could not be plowed so farmers sowed in the rain, scything weeds to hide the seed from birds and mice. By Divine Grace a crop was made, only two thirds of normal harvest but sufficient to forestall general famine among the tenants. Tithes were not collected this autumn and the Church distributed alms and acorns to the poor. Annals of the Abbey of Saint Marien [Lake Constance, Germany] Anno Domini 1340
How To Do It: Find the weediest field possible. Broadleaf weeds are best and thistles best of all. (Thistles indicate fertile soil). Broadcast seed directly into standing weeds. (Pelleted seed greatly increases seedling survival, especially for large-seeded crops like peas and beans). Mow down weeds with a scythe (or use a lot of people with sickles or machetes). Cut weeds act as mulch for germinating crop. Pray for rain. Come back at harvest time and hope for the best. Yields are low but surprisingly economic (because there are no costs other than seeding and harvest).
Medieval No-Till Yields of Dry Peas: Poor Crop: 4 to 5 bushels = 250 to 300 pounds per acre. Average Crop: 6 to 8 bushels = 400 to 500 pounds per acre. Good Crop: 10 to 13 bushels = 600 to 800 pounds per acre.
Medieval No-Till Yields of Spring Wheat: Poor Crop: 4 to 6 bushels = 275 to 400 pounds per acre. Average Crop: 7 to 10 bushels = 440 to 650 pounds per acre. Good Crop: 11 to 17 bushels = 660 to 1,040 pounds per acre.
Sow-and-Go planting is ancient technology adapted for modern machinery. In India it is called Zero Budget Natural Farming. Australians use the term No-Kill Cropping. Some call it Do Nothing Farming, Zero Petroleum Agriculture, or Minimum Effort Agronomy. Less charitable souls use the term Subsistence Agriculture. Regardless of label, the principle remains identical: Sow seed (without tillage or any other investment) then forget about the crop until harvest time. Small fields are hand planted, large areas seeded with no-till drills. The trick is to sow when plants normally drop their seeds, usually during the dry or cold season when weeds are dead or dormant. Native vegetation is left standing; this is necessary to prevent erosion, feed soil organisms, aid water infiltration, slow wind speed, provide shade, increase humidity, improve biodiversity, and trap snow.
Sow-and-Go agronomy is particularly suited where climate or soils are problematic, especially drought-prone, semi-arid regions like Australia and the western prairies of North America. Old farms, hay fields, pastures, range lands, or any relatively flat area of grass or weeds is suitable for Sow-and-Go planting. For best results, no-till planters should have razor sharp coulters to slice through surface vegetation, chisel tines or cultivator shoes to open a narrow slot for seeding, and double press wheels to ensure good seed to soil contact. Minimal soil disturbance is essential for success. Pelleted seeds are recommended for broadcast planting or land restoration.
In years with good rainfall, Sow-and-Go crops typically yield 60% to 70% of conventionally grown plants. Translation: Expect 40% yield losses compared to full-tillage or herbicide treated crops. Higher yields are sometimes possible on particularly deep or fertile soils. Drilled crops generally yield more than broadcast seeded crops, especially when seeds are large, weather is dry, or when planting naked seeds.
Sow-and-Go cereal culture is the wave of the future. Farmers should set aside a few acres to test this new biological technology which can be used to grow any kind of small grain including pseudo-cereals like amaranth (Amaranthus caudatus), buckwheat (Fagopyrum esculentum), and quinoa (Chenopodium quinoa). If weedy fields are not available, seed mixed cover crops of annuals or perennials then plant into this artificial prairie. Soil fertility and structure improve rapidly under continuous vegetation, especially if legumes and root crops are included in the mix. Each year planting becomes easier and yield potential increases. Results are often surprising and cannot be easily predicted because of complex interactions between many species in a new, “designer ecology”. Careful observation, precise timing, and constant adjustment are needed to “tweak” the system to favor particular crops. Real ecological management is required — the very opposite of robotic, spray-by-calendar conventional agriculture. Sow-and-Go farmers are never bored; they are always making new discoveries in their fields.
For More Information
Readers who have any questions or require additional information about growing crops in weeds should contact the Author directly:
Eric Koperek = firstname.lastname@example.org
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 the development of new crop varieties).