Summer squash is a tasty treat found in the spring and summer times at farmers market and produce stands. Summer squash will add flavor to and enhance the taste and enjoyment of many popular dishes. With some effort and work on your part you can grow your own summer squash and this article will serve as a guide to help you get started.

Summer squash belongs to the C. Pepo species which also includes many pumpkin varieties. Summer squash varieties include: the thin neck type which include crooked and straight cultivars, the scallop type which are thinner, flat and rounded in appearance, and the curved marrow type which includes zucchini.

Which ever of these cultivars you choose to grow you can usually find good seeds from reputable sellers at local garden shops and through online and mail order seed catalogues. While there are a lot of varieties to pick from, in general if you select heirloom and older varieties, you will have fewer insect problems and usually produce a more abundant crop.

Summer squash plants should be grown in a location with full sun and well draining soil. The soil would ideally have a pH of 6.0 – 7.0. Before planting, it not already present, apply and incorporate organic matter in to the soil. Performing a soil test is the best method to determine nutrients present in the soil, but if not available, apply a balanced fertilizer containing Nitrogen, Phosphate, and Potash prior to planting. Follow fertilizer recommendations but avoid further applications when pollination begins. Make sure plants receive water or rainfall amount of 1 – 2 inches weekly throughout the entire season.

Since summer squash is a warm weather crop, plant seedlings or direct sow seeds after the last frost in your region. Temperatures of 70° Fahrenheit and above will allow for seed germination to occur. Seedlings and seeds can be planted in hills of 2 – 4 seeds with 12 – 15 square foot per hill. Summer squash seeds can be planted anytime throughout the summer as long as enough time is given to produce and harvest fruit.

Some form of control should be used to protect plants from insect and disease damage. Many diseases can be controlled using copper based fungicides. Insects, primarily cucumber beetles and squash bugs are among the most harmful to summer squash plants and fruit. These insects feed on plant nutrients and are vectors that introduce disease to plants including bacteria wilt. Applying Neem oil and Garlic Barrier are safe and effective insecticide products to use. The use of insect resisting floating row covers also provides effect control of these insects, however during pollination time access must be provided for bees to pollinate fruit. It is fortunate however, that summer squash plants set and produce harvestable fruit very quickly, which reduces fruit exposure time to insects minimizing over all damage.

Summer squash plants will begin to produce harvestable fruit at 45 – 55 days and continue producing fruit for several weeks thereafter. Summer squash fruit is harvested while fruit is technically still immature, so plan to harvest early. For maximum eating quality, thin neck and marrow type varies should be harvested when fruit is approximately 7 – 10 inches in length and when fruit diameter is about 1.5 inches or more. Scallop type varieties should be harvested when fruit is 4 – 6 inches in diameter for best taste. Fruits will usually be ready to harvest about a week after pollination. Slightly overly mature fruit can be eaten but it is less desirable, when identified, overly mature fruits should be cut from the vine unless you want to produce seed. Although not as desirable to eat, overly mature fruit, unlike immature fruit will produce mature seeds that can be saved to plant later. Checking plants at least once every two days is a good way to ensure that fruits are harvested at the right time.


Growing Summer Squash, Fact Sheet 472; Maryland Cooperative Extension

Revised by: Pamela B. King, Extension Agent

Watch Your Garden Grow, Summer Squash; University of Illinois Extension

Ron Wolford, Unit Educator, Urban Horticulture and Environment; Drusilla Banks

Extension Specialist, Food Science and Nutrition Programming