What Is It? Rototillers use revolving vertical blades to pulverize and mix soil (much like a kitchen blender). Rototillers create a fine, smooth seedbed ideal for small-seeded crops. Rototillers are also useful for one-pass field operations as no other tillage implement is needed to prepare ground for planting.
Do Not Confuse With: A similar tillage implement called a “Roterra” or “Rotary Plow” uses horizontal blades designed NOT to mix soil layers.
Motive Power: Most rototillers are self-propelled or attached to the PTO = power-take-off of a farm or garden tractor. Horse drawn rototillers are also manufactured with rotary tines powered by gasoline engines.
Front Versus Rear Tines: Many garden rototillers are built with tines mounted in front of the wheels. Front-tine models are NOT recommended as they are difficult to control and operate inefficiently. Only purchase rear-tine rototillers for farms or large gardens.
Forward Rotating Versus Contra-Rotating Tines: Rear tined rototillers may be purchased with either forward rotating or backward rotating = contra-rotating tines. Forward rotating tines turn in the same direction as the tractor wheels. Contra-rotating tines turn backwards while the tractor wheels turn forwards. Forward rotating tines are best for green manuring = chopping plants into small pieces and mixing them with the soil. Contra-rotating tines are best for sod busting = tilling soils that are hard or have never been broken (plowed). Most farmers and gardeners buy rototillers with front rotating tines because these machines are more versatile and till faster than contra-rotating models.
Tillage Width: Most garden rototillers till strips 16 to 22 inches wide. Garden tractor rototillers till 4 foot wide strips. Rototillers sized for farm tractors till strips 8 feet wide.
Tillage Depth: Most rototillers reach 8 inches deep. Front tined rototillers have poor depth control and are not recommended for shallow tillage or cultivation. Most rear tined rototillers have good depth control and can be set to till in 1-inch increments.
Hard Ground: Rototillers are not sod-busters; they are ill-suited for tillage in hard, rocky, or stony fields. Average wear and replacement of rototiller tines is much higher than for chisel plows, disc harrows or other tillage implements. It is better to use a moldboard plow to break hard ground then “harrow” with a rototiller. Alternatively, use a rototiller with contra-rotating tines to bust hard soils into soft seed beds.
Wet Ground: Rototillers should NEVER be used on wet or moist fields. Ideal soils are slightly dry or barely damp. Correct soil moisture is critically important for good tillage results. Rototillers will churn overly moist soils into a paste-like texture that will harden like concrete. One pass with a rototiller is sufficient to create a dense, impervious plow pan that will greatly restrict root growth and crop yields. Improper rototilling can ruin a good field so always wait until soil is well-drained = nearly dry.
Mow First: Rototiller tines are easily clogged by surface litter, especially tough grass or weed stems. Always mow fields before rototilling or use a forage chopper to shred standing vegetation. Flail mowers, rotary mowers, and common lawn mowers do the best job of chopping plants into small pieces.
Cover Crops: Rototillers are ideal tools for incorporating large amounts of organic matter into the soil. Mow cover crop first then drive slowly so tines can thoroughly chop and mix crop residues into the earth. Grow multiple cover crops in sequence to eradicate problem weeds or improve soil fertility and structure. Buckwheat (Fagopyrum esculentum) is an excellent cover crop for farm and garden: It overwhelms weeds, has an extensive system of fine roots that improve soil tilth, and has soft stems and tender leaves that are easy to rototill into the ground.
Tillage Speed: Always till slowly so tines have sufficient time to chop and blend soil uniformly. Low tractor speeds produce the best results.
Deep Tillage: In heavy clay soils it is better to make multiple passes rather than trying to till 8 inches deep all at once. Set rototiller 2 inches deeper for every pass.
Carrot Farming: Rototillers are ideal for preparing planting beds for carrots and other crops that need fine, loose soil. Apply soil amendments sequentially (peat first, sand second, fertilizer last) then rototill after each application. Set rototiller 2 inches deeper for each succeeding pass. 4 passes are sufficient for most soils.
Mixing Potting Soil: Large quantities of potting soil are easily prepared with a rototiller. Spread ingredients on bare ground then mix by making multiple passes with rototiller set to skim soil surface (1 inch deep). 1 part topsoil + 1 part peat + 1 part sand = 3 parts by volume is a good, general purpose potting mix suitable for most farm, garden and greenhouse crops.
One-Pass Farming: Broadcast lime, fertilizer, seed, and herbicide (if desired) over weeds or other cover crop. Mow closely then rototill only 2 inches deep leaving soil surface rough and trashy. Irrigate to firm seedbed or wait for rain. Some seeds will be buried too deep, others too shallow, but enough will germinate to make a crop.
Winter Grains: The one-pass technique is ideal for growing winter wheat, barley, oats, or rye. Broadcast Dutch White Clover (Trifolium repens), Red Clover (Trifolium pratense), or Crimson Clover (Trifolium incarnatum) along with winter grain seed. Clover will suppress weeds without need for chemical herbicides. Note: If soil is too wet, plant without tillage. Seed will work its way into the ground and surface mulch will protect germinating seedlings. Many sprouts will die but enough will survive to reach target yields. (Good Farming Practice: When planting into standing vegetation on un-plowed ground, sow pelleted seed to increase germination and seedling survival).
Truck Farms: A rototiller is the only tillage implement needed for truck farms and market gardens. Farms up to 25 acres can be managed using only a rototiller and mower.
>>> Till only as deep as necessary to get seed or transplants into the ground. Excessively deep tillage wastes time, energy, and harms soil structure. Shallow tillage is the best way to prevent formation of plow pans = compacted soil layers.
>>> Never rototill vegetation higher than the tines = 8 inches tall. For best results, always mow or chop plants before rototilling.
>>> Never rototill wet soil! Be patient and let ground drain. Till only when earth is barely damp = almost dry. Rototilling wet fields destroys soil structure.
>>> A rototiller is like a kitchen blender — it is best used when soil needs to be uniformly mixed. It takes time to pulverize earth into a fine, soft seedbed. Drive SLOWLY or the field will have to be re-tilled.
>>> It is often unnecessary to till an entire field. Rototill only where seeds or transplants will be set. Leave the remainder of the ground covered by weeds, clover, or other nurse crops. This technique is ideal for widely spaced vine crops like tomatoes, pumpkins, melons, squash, sweet potatoes, gourds, and cucumbers.
>>> Improperly used rototillers kill large numbers of earthworms. To conserve earthworm populations till only when essential (avoid tillage whenever possible), till shallowly, and till in the afternoon when ground is warmest and earthworms have moved down to cooler soil depths. Remember: More earthworms are always better than more tillage.
>>> Rototilled soil is finely pulverized which makes it very susceptible to erosion. Use good conservation practices to prevent soil loss on slopes or in areas with high winds or severe rainstorms. Plant windbreaks, till only on the contour, leave wide sod strips between tilled areas, and top seed low growing clovers over cash crops to protect the soil surface.
>>> Use rototillers with forward rotating tines for green manuring, soil preparation, and cultivation. Use rototillers with contra-rotating times to “plow” hard or heavy soils for planting Note: Even the most rugged rototillers are not designed for heavy-duty tillage. On problem soils it is best to use a moldboard or stone plow to break the land first then harrow with a rototiller. This prevents unnecessary wear and replacement of rototiller tines.
Would You Like To Know More? Please contact the Author directly if you have any questions or need more information about tillage implements and practices.
ERIC KOPEREK = email@example.com
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 greatly speeds development of new crop varieties).