10 Corn Companion Plants You Should Grow Nearby

Corn is part of the epitome of companion planting, the Three Sisters, where corn, beans, and squash are planted together for mutual benefit. The method originated in North America and has been practiced for more than 3,000 years. In addition to beans and squash, there are other good companion plants for corn.

Here is a list of good companion plants for corn, as well as a list of bad neighbors that should be avoided.

What Is Companion Planting

The idea behind companion planting is to plant different plants near one another for mutual benefit—deterring pests, attracting beneficial insects and pollinators, and balancing the nutrient, water, and light requirements of plants so they won’t compete.

Keep in mind, though, that companion planting is mostly based on observations and anecdotal evidence rather than hard facts or scientific studies. That also explains why you will often find conflicting information about good and bad.

Good Companion Plants for Corn

Beans

Beans and corn are classic plant companionship because the two crops mutually benefit each other. Beans have a symbiotic relationship with soil bacteria called rhizobia. These bacteria draw atmospheric nitrogen from the air and convert it into ammonium nitrogen, a form of nitrogen that can be absorbed by nearby plant roots. In return, the legume provides carbohydrates to the bacteria. By planting corn and beans together, the corn gets additional nitrogen from the beans. This is true for all types of beans, bush beans, as well as pole beans.

The corn serves as a natural trellis for the beans. The corn plants are sturdy and tall enough for the beans to grow and wrap around them. And the timing is just right—both corn and beans grow rapidly in mid and late summer.

Garden Peas

What applies to beans also applies to garden peas—they fix nitrogen in the soil, which benefits the corn. Although peas are a spring crop, planted as soon as the soil can be worked, and corn is a summer crop, the corn still benefits the peas. When the corn starts growing in the early summer, it provides the established pea plants with welcome shade on hot, sunny days.

Cucumbers

There are several mutual benefits of growing corn and cucumbers together. Both are summer crops that share similar growing conditions; they need warm soil and ample moisture but don’t compete. But timing matters—select early-maturing corn varieties such as Early Sunglow.

The tall corn provides shade for the cucumber plants and the stalks can serve as a natural trellis for the cucumber vines to latch onto, which keeps the cucumbers off the ground where they are more prone to rotting in wet weather as well as insect damage.

The cucumber vines cover the soil around the corn plants, keeping it cool and conserving soil moisture. Because cucumber vines are so dense, they also do a great job suppressing weeds. Proper spacing is also important. Space cucumbers and corn seedlings 12 inches apart.

Summer Squash and Zucchini

What applies to cucumbers also applies to summer squash and zucchini. The sprawling plants keep the soil around the corn plants moist and cool and choke out weeds, and the corn stalks can serve as a trellis.

Melons and Watermelons

The fruit of most melons and watermelons are too large and heavy to be sustained by corn stalks, but they still make good companion plants for corn, covering the base around the plants with the dense foliage so no weeds can grow, and the soil stays cool and moist.

Best and Worst Companion Plants for Watermelons

Winter Squash and Pumpkins

Planting winter squash and corn together is part of the classic Three Sisters companion planting. The large leaves of the squash vines keep weeds out and improve soil moisture retention. Winter squash and pumpkin benefit from the dappled shade of the corn stalks.

Lettuce

Most lettuce varieties don’t grow well in the summer heat, growing it next to corn where it gets welcome shade lets you grow lettuce all summer long without it bolting or tasting bitter.

Potatoes

Although tomatoes and eggplant should not be planted next to corn, this member of the nightshade family is a good companion. The growth habits of potatoes and corn are just the opposite—potatoes take up mostly underground space whereas corn, which has shallow roots, towers aboveground. Growing them maximizes garden space.

Dill

Plant dill next to your corn for natural pest control and let it flower because it is at that stage that dill attracts the most beneficial insects including as ladybugs, hoverflies, and lacewings, which feed on aphids. It also draws parasitic wasps, which prey on hornworms.

Nasturtiums

These annual flowers have a double effect on nearby corn plants: nasturtiums deter pests, from aphids to whiteflies and larger pests like beetles, and, if you plant a vining variety, their dense foliage suppresses weeds, retains soil moisture, and keeps the soil cool.

Plants to Avoid Growing Near Corn

Avoid planting any of the following next to corn:

1. Tomatoes: Corn and tomatoes are sought out by the same or similar pests, such as tomato hornworms and corn earworms, which will both feed on either plant. When planting tomatoes and corn. keep as much distance between them as possible to limit the spread of an infestation. Tomatoes and corn also compete for nutrients and sunlight.

2. Eggplants: They fall into the same category as tomatoes. Eggplants attract tomato hornworms and compete for nutrients and sunlight.

3. Cruciferous vegetables: Cabbage, broccoli, kale, cauliflower, kohlrabi, brussels sprouts and other members of the cabbage family are bad companions for corn because they are heavy feeders and compete with corn for nutrients. Corn also casts too much shade on these plants, which need full sun.

As a rule, avoid fruits and vegetables that won’t grow well in shade cast by tall corn plants.

Read the original article on The Spruce.