Companion Planting for Healthy Vegetable Plants

The idea of companion planting goes back many years and rests on the theory that some plants benefit from being planted next to something different. Using plants for trap crops to keep a certain bug off a cash crop is an example of companion planting. I use vegetable amaranth to attract the cabbage looper and Colorado potato beetle. They will not go to anything else if I have vegetable amaranth around the garden. Another example is the use of legumes to fix nitrogen in the soil for neighboring plants such as planting beans with corn, which loves nitrogen. If you are weeding and come across a weed that is devoured by bugs or has leaves riddled with holes, don't pull it up. You've got a trap crop. You can watch it to see what bugs are eating it and then douse them with insecticidal soap or pyrethrum when they're gathered for breakfast.

Sometimes a plant will exude a chemical that will repel pests, such as marigolds secreting a substance that repels nematodes. Planting tall corn over shade tolerant vines like squash can help confuse the squash vine borer and the tangled vines may help keep deer and raccoons off the corn. Planting squash on the south side of the row makes it easier to harvest the corn.

Mixing plants together will create a biologically diverse area known as a "refugia" that allows beneficial insects to thrive. Lastly, diversity in the garden guarantees that if one type of plants succumbs to heat, cold, or disease, others can simply take its place.

Here is a short list of some popular vegetables, their companions and the plants to avoid planting alongside or in the same place the previous season:

Asparagus-Basil, tomato, parsley. Bad companions-onions.

Pole Beans - Most vegetables and herbs. Avoid onion, garlic, fennel and basil.

Bush Beans - Corn, potatoes, cucumbers, and corn. Avoid onions.

Cabbage - Mint, potatoes, onion, dill, and rosemary. Avoid tomatoes and pole beans.

Carrots - Onions, peas, lettuce, and tomatoes. Avoid dill.

Corn - Potatoes, beans, peas, cucumbers, pumpkin, squash. Avoid Tomatoes.

Cucumbers - Sunflowers, radishes, Corn, beans. Avoid potatoes or herbs.

Tomatoes - Onions, carrots, parsley, chives. Avoid cabbage and potatoes.

Onions and Garlic - Tomatoes, beets, lettuce. Avoid Peas and Beans.

Potatoes - Beans, corn, cabbage. Avoid pumpkin, squash and cucumbers.

Plants that are great for pest control at any time are marigolds (except for spider mites), onions, chives, dill, thyme, oregano, mint and petunias. In fact, most herbs that have a heavy scent will repel pests. Wormwood repels everything, but secretes a substance that supresses the growth of other plants around it. For controlling moles, plant lots of daffodils, jonquils and paperwhites around the garden because their bulbs will stay underground all summer and moles and gophers will never eat one. The bulbs are cheap, too! Another plant to try for mole control is Fritellaria, although the bulbs are quite expensive. A great book for more information on companion planting is: Carrots Love Tomatoes: Secrets of Companion Planting for Successful Gardening by Louise Riotte.

More gardening information and sources of books, bulbs, and plants at: http://www.biglump.com