In a home vegetable garden, crop rotation involves changing the planting location of vegetables within the garden each season. Crop rotation is used to reduce damage from insect pests and to limit the development of vegetable diseases by interrupting pest and disease cycles. Crop rotation also helps manage soil fertility by returning nutrients to the soil without synthetic inputs.
Although crop rotation is usually geared toward large conventional farms, the lessons are the same for the home vegetable garden. As many large commercial farms plant the same crop, year after year, more chemical fertilizer, insecticide, fungicide, spectracide, and herbicides are needed. This will happen in the home garden as well.
A three-year cycle can be used, but even this can become complicated for those with limited planting areas, so moving your plants even a few feet from where they were last season will be beneficial for the plant's health. A simple plant rotation might look like this:
Year 1 - tomatoes - beans - squash
Year 2 - squash - tomatoes - beans
Year 3 - beans - squash - tomatoes
Fall and Winter can also be a time to take a break. After a brutal summer of fighting pests and disease, your soil is hungry and depleted. Cover crops are a good way to help build your soil structure and fix nitrogen after they are tilled under and left to decompose for about 3 weeks before planting in the spring. Examples of cover crops or “green manure” are clover, radish, rye, wheat, and oats. An added bonus is that their flowers attract many pollinators and beneficials. If a cover crop is not your thing, make sure you amend with rich compost or leaf mold by adding a nice 2-3 inch layer before you plant your cool-season garden.
Don’t be in a hurry to plant your cool-season garden. October is known for having some very warm days and Santa Ana winds, which will have ill-effects on many cool-season vegetables. Very late October or even better yet, November is a good time for planting greens of all kinds, broccoli, brussel sprouts, and herbs. A recent article by Nan Sterman says, “Are you anxious to get planting? I do understand how you feel, but....it isn’t time yet. Days are way too warm, so the stress on newly installed plants is still huge - which translates to dead or very weakened plants. Be patient. Planting now is still really risky. Wait till it feels like fall both at night and during the day. You will have far greater success (and less frustration) if you wait.
For more information on vegetable garden crop rotation can be found at http://hort.extension.wisc.edu
by Suzanne Kestell and Lisa Pavel