Ohio organic vegetable growers mostly rotate among general vegetable families – solanaceous (many referred to this group as the "nightshades"), legumes, squash or curcurbits, leafy greens, brasssicas, and root crops. These rotations usually occur simultaneously each season by entire fields within a farm or individual beds in a single field. If there is some concentration on particular groups, e.g., curcurbits and solanaceous, then there may be only a three-step rotation – curcurbits/solanaceous/all other families.
Nearly all the vegetable producers grow a cover crop between growing seasons, usually a small grain such as winter rye or wheat, which is turned under in the spring. A small portion include hairy vetch with the small grain as green manure.
Approximately 15% of the vegetable growers stop growing vegetables completely in a field or bed for a period of one to two years. In the interim years between vegetables, a clover crop or a grain crop may be grown.
Specialty crop growers, e.g., ginseng or flower bulbs, reported alternating with another unrelated specialty crop or leaving the ground fallow for approximately two years.
Field-crop producers reported rotations ranging from two years to seven years in length. Rotations including hay (usually alfalfa or clover) varied by a year or two, depending on the outcome of the hay. In general, the frequency of year-lengths were: two years, 6%; three years, 35%; four years, 43%; five years, 13%; six years, 2%; and seven years, 2%.
The most frequent field-crop rotation reported was corn-soybeans-small grain (winter wheat, spelt, or winter rye sown in the third year) mixed with clover. In the spring of the fourth year, the grower would either turn in the cover crop for green manure going into corn or let the small grain and clover develop into a hay field.
In 75% of the field-crop rotations reported, corn and soybeans were in the rotation. Corn immediately preceded soybeans in 83% of these cases, soybeans immediately preceded corn in 13%, and at least one crop separated the two in the remaining 4%. Corn was never reported to be grown two years in a row.
A small grain, usually a winter small grain such as wheat, spelt, or rye, was included in 87% of the field-crop rotations. When small grain types were identified (several respondents only wrote "small grain"), winter wheat was mentioned 42% of the times, spelt 33%, rye 13%, and oats 11%.
Sixty-three percent of the field crop rotations had at least one year of hay in the rotation. Twenty-two percent maintained two or more years of hay. As may be expected, respondents who have organic livestock operations were more likely to incorporate hay into their rotations – 81% of organic livestock producers grew at least one year of hay whereas 50% of the producers without organic livestock did. Of the organic livestock producers, 33% maintained two or more years of hay. Of the ones without organic livestock, 14% maintained two or more hay years.
The general term "hay," with no indication of forage type, was used by 47% of the producers using at least one year of a hay crop in their field-crop rotations. Clover was specifically identified as the hay crop in 21% of these rotations; however, in only two situations was the clover specifically identified as red or sweet clover. Alfalfa was named as the hay involved in 21% of hay rotations as well. Clover mixed with grasses was named 6% of the time, and clover mixed with alfalfa and grass was mentioned in 4% of the rotations including hay.
Buckwheat was used in 9% of the vegetable rotations reported, and then it was only used as an optional green manure cover crop. Buckwheat was found in only 3% of field-crop rotations and was harvested as a crop in those cases.