As my spring garden season approaches, my mind is filled with visions of splendor. With a freshly tilled garden, I can see my plants grow lush and full, their bounty promising a fruitful harvest. What do I want to grow this year? More important question, What do I want to eat?
Tomatoes. Or should I say, pasta sauce. I’ve been having such good luck with my tomatoes that I might increase the yield this spring. Second? Beans, of course. Who doesn’t love beans? And onions–but not in adjoining beds. No. These two do not care for each other and will not yield the fabulous crop of my imagination. Why not?
They’re not good companions in the garden and companion planting is KEY when it comes to organic gardening. What is it and why do we do it? In a nutshell–or bean pod–it’s organizing your beds according to plants that help one another, and steering clear of those combinations that don’t.
Companion planting is based around the idea that certain plants can benefit others when planted next to, or close to one another. It exists to benefit certain plants by giving them pest control, naturally, without the need to use chemicals. In some cases, plants can give one another a higher crop yield. Some are even touted to improve the flavor of neighboring plants. Take basil and tomato, for instance. Plant these “friends” together and your tomatoes will be even more delicious!
Backyard gardens use companion planting on a small-scale, but it can be applied on larger-scale operations. By having a beneficial crop in a nearby field that attracts certain insects away from the main crop, commercial growers have found the practice to be very beneficial. It’s called trap cropping.
While companion planting has a long history, going back to the Native Americans and their employment of the “Three Sisters,” the benefits have not always been understood. Sounds simple enough: plant corn and beans together, allowing the beans to climb the corn stalk while fixing nitrogen into the soil. Squash plants shade the ground, preventing weeds and retaining moisture. However, recent tests are proving scientifically, that this practice works!
The French marigold, along with other plants, is well-known for companion planting. It exudes chemicals from its roots, or aerial parts, that suppresses or repels pests, protecting neighboring plants. (My roses love marigold!)
Companion planting also exists in a physical way. For example, tall-growing, sun-loving plants may share space with lower-growing, shade-tolerant species, resulting in higher total yields from the land. This is called spatial interaction and can also yield pest control benefits. For example, the presence of prickly vines is said to discourage raccoons from ravaging sweet corn.
Nurse cropping is a method whereby tall or dense-canopied plants can protect more vulnerable plants through shading or providing a wind break. Oats have long been used to help establish alfalfa and other forages by supplanting the more competitive weeds that would otherwise grow in their place. In many instances, nurse cropping is simply another form of physical-spatial interaction.
Beneficial habitats-sometimes called refugia—have received a lot of attention in recent years. The benefit is derived when companion plants provide a good environment for beneficial insects, and other arthropods, especially those predatory and parasitic species that help to keep pest populations in check. (Ladybugs are super-beneficial insects, too!)
So as you contemplate your next crop, take companion planting into account and organize accordingly. It really will make a difference, particularly when it comes to alleviating trouble spots. From bugs to weeds, companion planting is the way to go. And anything that takes the “work” out of gardening is a friend to me. For an idea of who likes who in the garden, check out this list of companion plants compiled by Mother Earth News.