Would you like to improve your crop yield? What a dumb question that is! One of the reasons you grow your food in the first place is to save money on groceries. Perhaps another reason is to grow produce that is pesticide-free. By rotating your crops you can achieve both these goals.
Here are several reasons for rotating crops.Plants in the same family - peppers, tomatoes, eggplants, for instance - share common soil-borne diseases that build up in the soil if there is a susceptible host. Related plants are prone to similar pests and use up many of the same nutrients. This can create deficiencies for the next planting.
One rule of thumb is to follow heavy feeders with light feeders and vice versa. If you have heavy feeders such as tomatoes, the soil will be low on nutrients. You can plant beets, or other light feeders such as mustard greens or leeks, in a nutrient deficient plot.
A well-planned rotation cycle can stop harmful microbes. Grow cabbage family crops after onions, for example. Onion skin emits a compound that stops plant parasites. Rotation will also prevent the buildup of soil nematodes and will help eliminate the chance of verticillium wilts, bacterial wilts and brown rot on potatoes.
Keep companions together. Cabbage and dill are planting buddies because as dill flowers, it draws beneficial insects that eat cabbage worms and aphids. Do not forget flowers. Annuals such as calendula planted near cucumbers and squash attract pollinators and that increases yields.
You can save money on fertilizers by relying on a rotation crop. If you grow a heavy nitrogen feeder such as sweet corn, follow it with peas or beans. They don't need added fertilizer because they work with the soil bacteria that fix nitrogen from the air in nodules on their roots.
Now you know why to rotate crops. Let's get started. Start by making a list of all the crops you want to grow and group them into families.
Family groups are:
Beets, spinach, Swiss chard
Cabbage, Brussels sprouts, cauliflower, collards, kale, kohlrabi, mustard, radishes, turnips
Carrots, celery, chervil, cilantro, dill, parsley, parsnips
Lettuce, sunflower artichoke, chicory, endive
Onion, chives, garlic, leeks, shallots
Peas, beans, lentils
Squash, cucumbers, melons, pumpkin
Now draw a map of your garden bed and divide it into equal areas. To make crop rotation work, you want to plant crops from different families in each section of your garden from one year to the next. This allows three or more years before you grow crops from the same family in a section.
Don't forget to include cover crops as part of our soil rejuvenation plan.
"Different cover crops offer different benefits," says Eric Sideman of the Maine Organic Farmers and Gardeners Association. "Legumes like alfalfa, clover and vetch fix nitrogen, grasses like oats and rye add organic matter and hold nutrients already there, and buckwheat competes with weeds."
Here are some sequences to try.
Grow cabbage family crops after onions, leeks or garlic. The reason for this is that the onion family crops thwart parasites that trouble cabbage.
Grow carrots, onions, or other root crops after winter squash or pumpkins. Vining crops smother weeds, making it easier to keep root crops clean.
Grow eggplant, potatoes or tomatoes after mustard or turnips. The cabbage family residues help to rid the soil of pathogens that attack nightshades.
Grow garlic and shallots after potatoes. A potato harvest will result in a clear planting bed for fall planting.
Grow lettuce after carrots or parsnips. These roots will loosen the soil and make preparation easier for shallow rooted lettuce.
Grow okra after you have grown marigolds. Marigolds exude substances from their roots that deter nematodes.
Grow peas, beans or clover after any cabbage family crop. Legumes fix their own nitrogen. Turn cover crops under to replace nutrients used by heavy-feeding crops.
Grow potatoes after corn. Corn as a preceding crop increases potato yield.
Rotating crops is the oldest and most economical way to control plant diseases.
Happy harvests to you!