Last year, I planted arugula seed between the short rows of onions, and the leafy, fast-growing arugula rocketed up and overpowered any weeds that dared to show their heads. The arugula grew relatively pest-free too! The arugula was ready to harvest just when the onions needed room to grow. In a eureka moment, I realized that I had discovered a vegetable companion-planting partnership that I could use year after year to make my garden healthier and more productive. Cool! The arugula helped the onions by keeping the weeds at bay and the onions helped the arugula by keeping the pests away.
Companion planting is little more than knowing that certain plants can benefit others when planted in near proximity. It is literally defined as “the establishment of two or more plant species in close proximity so that some cultural benefit (pest control, higher yield, etc.) is derived.” Scientifically speaking, companion planting embraces a number of strategies that increase the biodiversity of agricultural ecosystems, which basically means it works well in the garden. In layman’s terms, though, it is simply two or more plants helping each other out in some fashion.
It’s helpful to think of building good plant communities when planning your garden. This is the most important concept behind companion planting. Time-tested garden wisdom holds that certain plants grown close together become helpmates for each other, thus making the gardener’s work easier. Plants need good companions to thrive. Except for growth and fruiting, plants are relatively idle objects. They are rooted in one spot and don’t seem to have much control over their environment. In fact, however, relationships between plants are varied - similar to relationships between people. In plant communities, certain plants support each other while others, well, just don’t get along. Plants, like people, compete for resources.
As a gardener, you’re both the mayor and the city planner for the city that is your garden. By growing plants with good companions, you bring peace and prosperity to your town. Plants, like people, want good neighbors.
As in city planning, the way you lay your vegetable garden out is crucial. Avoid planting vegetables in large patches or long rows and interplant with flowers and herbs. Large groupings of one type of vegetable serve as a beacon, calling out to any nearby problematic pests. If, however, you mix in flowers and herbs, it becomes more difficult for pests to find your veggies. The scent of flowers and herbs, as well as the change up in color, has been shown to confuse pests. Certain flowers and herbs attract beneficial insects to your garden. Plus adding flowers to a veggie garden or adding vegetables to the flower bed is a quick and easy way to add beauty and interest to your yard.
Almost any article on companion planting references the Native American “Three Sister Planting System.” This age-old grouping involves growing corn, beans and squash – often pumpkin - in the same area. As the corn stalks grow, beans naturally find support by climbing up the stalk. Beans, as all legumes, fix nitrogen in the soil, which supports the large nutritional needs of corn. Squash grows rapidly and the large leaves shade out weeds and serve as natural mulch, cooling the soil and slowing evaporation.
Many long-time gardeners swear that growing certain plants together improves flavor as well. While science hasn’t found support for some of the benefits of companion planting, there is support for the above information.
Historically, North American and European gardeners based many of their attempts with companion planting on widely published charts, which were mostly derived from funky chemistry experiments using plant extracts in the 1930s. But it turns out many of the plant partnerships listed in these “traditional” companion-planting charts don’t actually work well. Reaping the benefits of companion planting is possible, though, as long as you look to time-tested crop combinations. I’ve tried to make this easier for you by making available my “Ultimate Guide to Companion Planting” at this link.
As for me, I love companion planting for its ascetic value, while I find any garden beautiful (yes, even my great granddad’s plowed rows), I find nothing more appealing than a multitude of plants growing in a small community of nature.