Companion Planting Is a Smart Idea with a Long History

Q: I’m trying to reduce my use of chemicals, such as synthetic fertilizers and pesticides, in my garden. A friend recommended companion planting, in addition to using organic products. What do you suggest I do to get started?

A: Not only does companion planting work, it’s also smart gardening. You can save both time and money by grouping plants together that encourage each other to grow more robustly, attract beneficial insects and pollinators, or repel pests known to favor certain neighbors. Sometimes it’s the odor or aroma of a plant that offers protection for its companions. Other times, it’s secretions from the root of the plant that build up in the soil. Occasionally, it’s both.

Early European settlers learned to plant beans and corn together from Native Americans, who showed them how the corn provides a structure for the bean vines to climb, enabling them to grow two crops in the space of one. The beans attract beneficial insects to eat many of the pests that prey upon corn and, as members of the legume family, also “fix” the nitrogen in the soil and make it available for other plants to use.

Certain combinations have been practiced for years, such as planting marigolds with tomatoes, which supposedly repels nematodes. But the effect is cumulative within the soil, so you have to plant marigolds with your tomatoes for a year or two, minimum, to reap the benefit. The pungent odor of old-fashioned marigolds may repel certain insects, too; some of the newer hybrids lack the smell the older varieties had.

Another well-known pairing is garlic with roses. Some gardeners have reported similar success by planting garlic chives near roses. Garlic chives thrive in our area, and they have an added benefit of attracting bees and butterflies when they bloom. Parsley and carrots also seem to offer protection for tomatoes. 

Some plants that make good culinary partners also make good garden partners, such as cabbage and dill. Dill tends to get tall and floppy and the cabbage heads lend support, while the dill attracts beneficial wasps that feed on cabbageworms. Basil and tomatoes, a classic pairing in the kitchen, are also a good garden duo. Beets and lettuce make a great salad and great neighbors in the garden. Collard greens go well with potatoes, on the plate and in the garden.

Some plants don’t play well with any others. Fennel is one such character. Whether you plant Florence fennel for its edible base or bronze fennel for its foliage, make sure you give it its own area of the garden, well away from other vegetables. Both make beautiful plants and butterflies love them.

Several books offer guidance on companion planting, but not all the advice they contain is appropriate for our area. You need to know what grows during which seasons here to get the most out of these resources.

For example, “Great Garden Companions” by Sally Jean Cunningham suggests planting nasturtiums with cucumbers, both to repel cucumber beetles and to attract predatory, or beneficial, insects that eat some of the bugs that cause problems. That’s great advice farther north, where cooler summers allow nasturtiums and cucumbers to thrive in the garden at the same time. Here in the Florida Panhandle, nasturtiums are a cool-weather edible flower and cucumbers are a warm-weather crop. The book still offers a lot of good general tips on companion planting, as long as you remember where you’re gardening. 

Another handy book on companion planting is “Carrots Love Tomatoes” by Louise Riotte. She advocates planting carrots and leeks together, because each seems to repel the flies that plague the other. Both grow during our cool season, so this works here. However, like Cunningham’s book, there are a few mismatches. 

If you’re not sure what grows when across North Florida, check out a great book by James Stevens called “Vegetable Gardening in Florida.” Stevens, a University of Florida professor who helped found the Florida Master Gardener program, specifies when to plant various vegetables in different areas of the state. You can also find advice for North Florida taken from Stevens’ book at the Leon County Extension Service’s website at http://bit.ly/180lwtc.