Vegetables are susceptible to a large number of diseases and insects. Companion planting is one way to promote healthy growth and repel pests without using harsh, toxic chemicals. Companion plants work together to help each other thrive and flourish, often resulting in a higher yield in crops. Use the right combination of plants in your garden and you'll be rewarded with healthy, chemical-free vegetables that you and your family will enjoy for months to come.
Plant peppers, onions, cucumber, beans, carrots and asparagus near tomatoes and you'll have a much healthier tomato plant. The asparagus and tomato are especially good companions. Asparagus plants release a chemical into the soil that is known to kill nematodes, which often eat the roots of tomato plants. In turn, the tomato plant repels the asparagus beetle, a pest that does a lot of damage to asparagus plants. Keep tomatoes away from potatoes, fennel and cabbage.
Beans, potatoes, onions, pumpkins and celery thrive when planted alongside corn. Bean plants often use the sturdy corn stalks as a trellis, eliminating the need for staking. Beans release nitrogen into the soil and corn absorbs the nitrogen through its roots, which promotes a healthier plant that may produce a higher crop yield. The pumpkin helps corn by smothering weeds and enables corn roots to retain moisture. Don't plant celery or tomatoes near corn.
Plant carrots around your tomatoes, beans, onions and lettuce plants. Carrots benefit from the nitrogen released by the beans. Tomatoes are helped by the carrot, but carrots are sometimes stunted by the tomato plant. The plant will produce a carrot that is smaller in size, but the flavor will stay the same. Carrots attract helpful insects such as the assassin bug and the lacewing who remove other pests that are harmful to vegetables. Don't plant dill, parsnip and radishes next to carrots.
The radish can be called the workhorse of the garden. It is a helpful companion plant to many vegetables including carrots, corn, squash, cucumber, lettuce, peas, beets, bush beans, pole beans and spinach. The radish protects squash plants from the squash borer and lures leafminers away from spinach. Radishes stop cucumber beetles and rust flies from harming your cucumbers. Letting radishes go to seed around corn will fight off corn borers. Radish does not mix well with the cabbage family.
Celery is a beneficial companion plant to leeks, cauliflower, onion, spinach, tomatoes and cabbage. Celery improves the growth of leeks, cauliflower and tomato plants. Cabbage finds celery beneficial as it repels the pesky white cabbage moth. Keep your celery and corn far apart in your garden.
Beets add minerals to the soil and are beneficial to the cabbage family, lettuces and onions. Beet leaves are 25-percent magnesium, which makes uneaten beets an excellent addition to your compost pile. Be careful when planting beets and beans together; runner beans, pole beans and beets stunt each others growth.