Many gardeners know that a diverse mix of plants makes for a healthy and beautiful ecosystem. Scientific study of companion planting has confirmed that some combinations have real benefits unique to those combinations. And practical experience has demonstrated to many gardeners how to mate certain plants for their mutual benefit. I don’t claim to be an expert in companion planting, but I’ve enjoyed experimenting in my own garden over the years because when you improve the health of your plants, you reduce the need for chemical intervention. That is music to the organic gardener’s ears!
How do companion plants work?
Every plant releases different chemical agents, either above ground through its leaves, or below ground from its roots. Every plant has special characteristics and growing habits. Companion plants provide one or some of the following benefits:
- Produce a chemical that deters pests that are attracted to its companion
- Produce a scent that reduces the pest’s ability to find its companion
- Attract the same pest as its companion (a.k.a trap crop)
- Provide food and shelter for beneficial natural pest predators
- Reduce weed seedling numbers, by shading or choking weeds
- Produce nutrients or growth stimulants for companion
- Provide support for climbing plants
- Provide shade for its companion
- Change or enhance companion plants flavor
I would like to highlight two of my favorite new companion plants. Using these two beautiful plants is making my life a lot easier in the garden.
Nasturtiums are a gardener’s best friend because they fend off garden pests from neighboring plants. It is a companion to radishes, cabbage family plants (cabbage, collards, cauliflower, kale, kohlrabi, broccoli and mustards), deterring aphids, squash bugs, and striped pumpkin beetles, and improving growth and flavor. Plant as a barrier around tomatoes, cabbage, cucumbers, and under fruit trees. Deters wooly aphids, whiteflies, cucumber beetles and other pests of the cucurbit family. Great trap crop for aphids (in particular the black aphids) which it does attract, especially the yellow flowering varieties. When the nasturtium is full of aphids, just pull out and discard. It likes poor soil with low moisture and no fertilizer.
In addition, nasturtiums produce decorative foliage, provide an ocean of brightly colored blossoms, and the entire plant is a tasty addition to salads.
Borage is an annual plant with gorgeous blue flowers and leaves with the flavor of cucumbers. It is considered an herb, but is often grown in vegetable gardens because the plant attracts bees and is considered a good companion plant for tomatoes, squash and strawberries. I planted borage near my tomato plant because it’s even supposed to deter my arch enemy…tomato hornworm. If that’s not enough, borage is said to enhance the flavor of tomatoes growing nearby.
Consider doing a bit of companion planting research as you make your fall garden plans. It’s very interesting, a lot of FUN, and a great tip for organic gardening.