Spring is in full swing and the first taste of summer is felt throughout the garden. With this, many vegetable gardens have already been planted, and some are beginning to produce their first fruits. But when you look at the garden, is it reaching its full potential?
When planting a small garden, the best thing to do is to use as much of the available space as possible. And the best way to do that is to plant companion plants. Companion plants are plants that complement each other, whether through their nutrient requirements, attracting or repelling insects, or other benefits, no matter how small.
Companion planting is a great way to grow plants more efficiently in small spaces and create a more aesthetically pleasing vegetable garden. There are many ways to plan and incorporate companion plants into the vegetable garden. There are more than those I will mention, but for that I will dwell on the easy and indispensable companions to include with your vegetables.
Basil is one of the easiest herbs to grow and the perfect companion to most spring and summer vegetables. Basil is an annual herb that grows best in warmer months and can be harvested until flowering.
With several varieties to choose from, there is a type of basil for just about any garden. There is some evidence that basil helps improve tomato growth and may help reduce thrips damage, although this may be limited. When they flower, however, they attract a wide variety of pollinators, insects beneficial to the garden. There will be some decline in some types of basil in the fall, especially cultivars susceptible to downy mildew, a common disease that affects basil. Once decline occurs, remove the plants and prepare for fall plantings of something else.
Nasturtiums are another easy-to-grow warm season annual with the added benefit of edible leaves and flowers. Nasturtiums are a beautiful flowering plant essential to associate with any cucurbit crop such as squash. There is some evidence that nasturtiums help repel squash bugs and cucumber beetles, with the main benefit being their attraction to beneficial insects. They grow well all over the garden and don’t require a lot of fertilizer, so heavier-feeding squash plants grow well alongside them.
The key is to kill them so they bloom for as long as possible.
Marigolds are often considered the ideal companion plant. They are warm season annuals that grow well with most vegetables, attract many beneficial insects, and are attractive plants to boot. One of the major misconceptions, however, is that interplanting marigolds will help repel nematodes.
Nematodes are harmful microscopic roundworms that can infest the roots of various plant species. While marigolds are effective in reducing the parasitic nematode population, you only need to have marigolds in a bed for this to be effective. That being said, marigolds still provide many other benefits for the vegetable garden and are encouraged to be used everywhere. I would encourage planting one of the regular varieties, as some hybrid or double-flowered marigolds may not attract as many beneficial insects.
Zinnias are another warm season annual that grow well in the heat of summer. Zinnias grow well with tomatoes, peppers and cucumbers. Although not often considered for the vegetable garden, these gorgeous blooms offer both an aesthetic enhancement and an excellent food source for pollinators and beneficial insects.
The main problem with zinnias is their susceptibility to powdery mildew, a common fungal disease in the landscape, but there are several types that are resistant to the disease. As with marigolds, plant single-flowered types as opposed to double-flowered types.
The concept of companion plants is complex and there is an enormous amount of information that can be explored. And of course there are more plants and more combinations to use and study. That being said, companion planting is always a great way to maximize a small garden. I would encourage looking into this concept further and of course creating a plan before planting and determining where there will be empty space to fill. No matter what you plant, however, the best thing to note is that the more flowers, the better the plants will fare and the richer the experience.
For more information on these plants and more, go to hgic.clemson.edu or contact your local cooperative extension agent.
Christopher Burtt is the Urban Horticulture Extension Officer and Senior Gardeners Coordinator for Berkeley, Charleston and Dorchester Counties. He can be contacted by email at firstname.lastname@example.org.