This is article that was written and published a couple of years ago.
By Debbie Roland, Compost Specialist
Companion planting is a good way to increase the flavor or deter pests. Here are a few examples of how and what to plant together.
Beans and peas increase nitrogen in soil and can be sown for harvest or as a cover crop. Don’t pull the plants out when the season is over, simply dig them back into the soil to replace nitrogen. Swiss chard, kale, lettuce and spinach all require extra nitrogen and can be planted with beans and peas.
Onions, garlic, leeks, shallots and chives repel cabbage worms and aphids. They can be planted with cabbage, kale, broccoli, cauliflower, tomatoes, carrots and peppers.
Marigolds, especially French Marigolds, produce a pesticide chemical from the roots which lasts long after the plant is gone. Plant with cucumbers, squash, and melons to repel squash bugs. Marigolds can be put in inexpensive pots and moved around the garden to help keep away pests.
Herbs such as basil, rosemary, thyme and sage, are said to enhance the flavor of tomatoes and repel hornworms, beetles and flies. Simply plant at the base of the tomato plant.
Radishes should be planted with plants that grow tall, like eggplants and peppers which grow slowly in cool weather. The radishes are fast growing and you can harvest them before eggplants reach their peak growing time.
Squash is one of the plants grown in the traditional Native American vegetable growing technique called the Three Sisters. The other two plants in the Three Sisters are beans and corn. Each plant had its role in this companion planting tradition. Corn served as a structure for the vining beans to grow up. Squash served as a ground cover to prevent weeds from growing. Beans provide natural fertilizer for all. Joseph Masabni, Assistant Professor and Extension Horticulturist; and Patrick Lillard, Extension Assistant, The Texas A&M System.