Healthy productive plants depend on proper soil, appropriate amounts of fertilizer, water, and control of pests. One cultural method to improve plant health is to avoid planting the same vegetable plants in the exact location every year. Each vegetable should be grown in a different place each growing season. This process is often referred to as crop rotation, one of the oldest practices in agriculture. It is one of the most effective tools for managing pests and maintaining soil fertility.
Vegetable plants can be classified into families. Tomatoes, potatoes, eggplant, and peppers are one family. Squash, cucumbers, and melons are another. The legume family contains peas, beans, peanuts, and soybean. Collards, cabbage, kale, and broccoli, which are popular in the year’s cooler months, compose the mustard family of plants. Onions, leeks, shallots, and garlic form another group.
Why is crop rotation so important? When vegetable plants are continually grown in the same place every growing season, plant disease and harmful insect populations build up over time in the soil and surrounding environment. Most plant diseases and insects are specific to one family of plants. Rotating the plants will help reduce the severity of these pests. For example, if you planted a section of your garden with tomatoes last year, use plants from another family, such as squash. However, remember potatoes, eggplants and peppers are in the same family as tomatoes, so they should not be planted in this location. Wait three years before planting the same family of plants at the same site for the best results.
Crop rotation has other benefits, such as improving soil fertility. The vegetable grown in a specific garden area impacts soil fertility there. Rotating the plants can even out the loss of different soil nutrients and allow time to replenish nutrients. Improvement of soil structure is another benefit of rotating different plant families. They frequently have roots that grow at various depths with varying cultivation techniques.
Rotating crops can be somewhat challenging in small vegetable gardens. Several options exist. You can grow only plants in the bean family for one year, followed by those related to tomatoes in the second year and the squash family in the third. Also, if you have enough space, another possibility would be to move the entire garden plot to another section of your yard the following year.
Another option is using cover crops, which are not edible but provide benefits such as improving soil structure and fertility and reducing weeds. Some commonly used cover crops are rye, wheat, millet, and buckwheat. At the end of their growing season, they are often tilled into the soil to build up organic matter that improves the overall quality of it. Certain cover crops, such as clovers and vetches, are leguminous plants. These plants have bacteria that reside in their roots and form a small nodule. The bacteria take nitrogen from the air and convert it into a form that plants can absorb. They release the nutrient into the soil, thus increasing the fertility of the soil in addition to improving the soil structure.
Crop rotation is an excellent way to improve the soil and reduce the buildup of pest populations. The process is relatively simple and has many benefits for the garden.
Timothy Daly is an Agricultural and Natural Resources Extension Agent with the University of Georgia Extension Henry County. He can be contacted at tdaly@co.henry.ga.us or 770-288-8421.
