Companion planting can be defined as the close planting of different species based on their ability to enhance one another's growth or offer some form of pest protection or other advantages. Sometimes this is a matter of choosing plants with different growth habits that don't compete with one another or those that have different nutrient needs that make efficient use of soil. Strategic companion planting is especially important in small gardens or wherever careful space planning is needed.
Zucchini and summer squash (both members of the Cucurbia pepo species of edible gourds) take up a lot of space in the garden, so it's a little challenging to find plants that work well with them. They tend to be heavy feeders and require regular, even watering. With that in mind, here are several plants that work well as companion plants for zucchini:
Good Companion Plants for Zucchini and Summer Squash
- Corn: Corn shares space well with zucchini and summer squash since it grows vertically while the squash grows along the ground. The squash plants also help shade the soil to reduce the weeds that compete with the corn plants. Both corn and summer squash have the same moisture and soil fertility requirements, so they are very good neighbors.
- Beans: Pole beans, especially, work well planted near zucchini and other summer squashes. They can be trained up a trellis, and like other legumes (peas, for example) their roots fix nitrogen to enrich the soil--a very good thing considering what heavy feeders zucchini can be!
- Nasturtiums and marigolds: Both plants act as a trap crop for pests such as flea beetles and aphids, so if you commonly deal with these pests in your garden, you may want to plant an edging of nasturtiums or marigolds around your summer squashes. They will distract the pests from attacking your summer squash plants.
- Radishes: Radishes are easily planted around zucchini and summer squash plants.They are said to repel many pests of zucchini and squash.
- Herbs: Many herbs, including peppermint, dill, oregano, catmint, lemon balm, marjoram, mint, and parsley, also help repel common insect pests of zucchini and summer squash.
Plants to Avoid with Summer Squash and Zucchini
- Potatoes: Potatoes have a bad impact on many vegetables, and summer squash and zucchini are among them. The main problem with potatoes is that they are root vegetables that take up a lot of soil nutrients. Members of the squash/gourd family often languish badly when planted near potatoes.
- Pumpkins: Although squash and zucchini can be grown near melons, they do not do well grown near pumpkins. As members of the same species, they may cross-pollinate in a manner that can affect the fruit.