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Problems Planting Zucchini With Summer Squash

By Barbara Fahs ; Updated September 21, 2017
Zucchini and summer squash can cross pollinate
squash on the grill image by jimcox40 from Fotolia.com

Dark green zucchini and golden yellow summer squash are tasty summer vegetables for many dishes. The plants, with their colorful, prolific fruit, also look nice in the garden. Other types of squash also are called summer squash. These include the pale green, scalloped patty pan, other varieties of zucchini, Italian marrows and varieties such as Zucchetta Rampicante and others. Winter squashes include the hard-shelled varieties such as acorn squash and Jack-o-lantern pumpkins.

Growing Zucchini and Summer Squash

Zucchini and other summer squash are among the easiest summer vegetables you can grow in your home garden. They need little additional fertilizer during their growing season if you plant them in soil you have amended with any type of compost. Be careful not to allow the leaves, blossoms or forming fruit to become wet—water all squash plants from below and provide shelter for them if your region receives summer rain. When blossoms and fruit become wet, this condition often leads to rotting. Also, wet leaves are more likely to develop fungal diseases.

Diseases and Insects

The same types of plant diseases and insects affect both zucchini and other summer squashes. If your zucchini plant develops powdery mildew, for example, this disease will quickly spread to other squash plants in the same area. If the squash beetle or another squash-loving insect invades one variety of squash, it won’t be long before it finds your other squash plants and proceeds to dine on them as well.

Cross Pollination

If you are a seed saver, be aware that any seeds you harvest from your zucchini or summer squash will most likely not reproduce true to type because these plants cross pollinate with each other. Zucchini and summer squash also cross-pollinate with winter squash, but not with melons, cucumbers and other members of the cucumber family. The squash that your zucchini and summer squash produce will be fine—it’s just their seeds that will be affected. If one of your neighbors is growing another type of squash within about 500 feet of your plants, cross pollination knows no property lines and it can occur in a stealthy manner.

Avoiding Cross Pollination

If you want to save your seeds for planting the following summer, plant your zucchini and summer squash about 500 feet from each other. This is a problem for many suburban vegetable gardeners because their yards are simply not that large. Another way to avoid cross-pollination is to stagger your planting times—allow only one variety of squash to flower at the same time. For most climate zones, this is a problem because by the time your zucchini begin flowering and producing squash, it will be too late in the season to plant summer squash. If you did plant this other variety of squash, you would need to pull out your zucchini plants. The best solution for those wanting to save their zucchini or summer squash seeds is to grow only one variety each summer season—and make certain your variety is not a hybrid because its seeds will not give you the same squash as the original plant.


About the Author


Barbara Fahs lives on Hawaii island, where she has created Hi'iaka's Healing Herb Garden. Fahs wrote "Super Simple Guide to Creating Hawaiian Gardens" and has been a professional writer since 1984. She contributes to "Big Island Weekly," "Ke Ola" magazine and various websites. She earned her Bachelor of Arts at University of California, Santa Barbara and her Master of Arts from San Jose State University.