Summer Squash for the Home Garden
Warm weather will be fast-approaching our region and now is the time to start squash seeds for your spring garden. Easy to grow, quick to mature, and full of flavor, summer squash is a great early-season vegetable that will turn any “brown thumb” into a successful gardener.
Before you get started, first consider the growing conditions for quash plants. A warm season vegetable, squash plants will not tolerate frost and require optimal soil temperatures between 60 and 85 degrees in order for seeds to germinate. Ideally, squash should be planted two weeks after the last projected frost date, which for our region is March 15. However, some more successful growers have a secret. If you want to get ahead of the insects and diseases that plague squash, and also have an earlier and prolonged harvest, start seeds indoors and transplant one- to two-weeks before the last projected frost date. If you have raised beds, you can pre-heat the soil by covering beds with plastic. This will also help knock down some early-emerging weed seeds.
Of course you will need to pay careful attention to the weather and be able to protect plants when frosts threaten this area. Plants set in the ground earlier in March can be protected with row covers or even with plastic buckets if you only have a few plants. Not only will setting plants in the ground earlier give you an earlier yield, it will also allow plants to become larger and withstand damage from cucumber beetles in March, as well as offset the emergence times of squash vine borers, which appear in late April.
Like most other vegetables, squash plants perform better in well-drained soils with high organic matter, and a pH of 6-6.5. If you are planting in raised beds, it is easier to get plants in the ground early, because the soil is less deep and warms more quickly than in-ground gardens. When choosing a site in which to plant, avoid areas that have had other cucurbit crops like watermelon, canteloupes, or cucumbers in the past three years. In poorly-drained soils, mound rows 5-8 inches above the ground in order to improve runoff. Plants should be spaced according to mature size, which is generally 36-48 inches for squash.
What varieties are available?
Cultivar selection of squash plants is vast, but is generally broken down into straightneck, crookneck, or zucchini varieties. Choose disease-resistant varieties when you are getting started, as there are many hybrid and flavorful options available. Some early-maturing varieties with excellent resistance include ‘Slick Pik’, ‘Cougar’, and the heavy-producing ‘Multipik’. If you prefer crookneck varieties, choose ones like ‘Dixie’, ‘Supersett’, or ‘Destiny II’. Some zucchini squash varieties to include in your spring garden plan include ‘Dunja’, a compact and spineless variety that matures early and has excellent resistance to powdery and downy mildews, as well as all mosaic viruses. If you prefer, ‘Noche’ is a larger plant up to 2 feet in diameter, but has heavy, prolonged yields and matures in only 45 days.
Emerging in late March, cucumber beetles attack squash at all stages of plant development. The best method of control for cucumber beetles is weed management around the garden, as these pests overwinter in weeds around garden edges. There might be nothing more heartbreaking than seeing a mature plant almost ready to harvest begin to wilt, which is the telltale sign of squash vine borer, a moth pest species that bores its way into the stalks of plants. Plant squash early to avoid this insect. Physical barriers like cheesecloth tied around the base of the plant are also effective, and will prevent larvae from chewing their way into stems. Avoid using tinfoil or other non-breathable material.
Early plantings will ensure that you avoid powdery and downy mildews, both late-season foliar diseases of cucurbit crops that coat the leaves of plants and inhibit photosynthesis. Avoid overhead watering in favor of drip irrigation to reduce leaf wetness and lower disease pressure. Fungicides are available but are preventative only and will not treat already-infected plants.
For more information on growing squash, visit http://ces.ncsu.edu, where you can post your questions via the ‘Ask an Expert’ link, or contact your local Extension office. If you live in Pender County, call 259-1235. In New Hanover County, call 798-7660. In Brunswick County call 253-2610.