Family: Cucurbitaceae
Genus and Species: Cucurbita pepo

Climate

Summer squash is extremely frost sensitive. Summer squash needs 3 months of warm, frost free conditions to produce fruit.

Soil

Summer squash needs fertile, aerated soil that is warm enough for germination (70°-90°) and warm enough for growing (65°-75°). Summer squash takes well to soil amended with compost or well-rotted manure. Summer squash grows best in soils with a pH between 5.5 and 6.5. Summer sqash needs moderate amounts of potassium and phosphorus and high amounts of nitrogen.

Spacing

Grow summer squash in a corner of the garden and train the vines to grow outside of the garden. Give summer squash about 2' apart in rows that are 2' apart.

Summer squash can also be grown in soil hills. To plant summer squash in hills, set one plant per hill and space the hills 4'-5' apart. Make the hills by mounding topsoil, compost, and well-rotted manure. Summer squash is a heavy feeder and when grown in these hills are more likely to get what they need.

Direct Seeding

Direct seed summer squash once the danger of frost is past and soil temperatures are between 70° and 90°. Use black plastic to warm the soil if needed.

Seeding For Transplants

Summer squash seeds can be started indoors one month before the last frost. Sow summer squash seeds in peat pots or cell trays 1/2" deep. Place the pot or cell trays under grow lights. Sow summer squash seeds 3 per pot/cell then thin to one squash plant once squash seedlings are established.

Germination

These seeds germinate best in soils around 70°F-90°F.
Germination will take 6-10 days.

Transplanting Into the Garden

Transplant summer squash starts when the soil is 70°-90°. Use black plastic to warm the soil. If using peat pots, slit the pots and place them into moist, warm soil. Water thoroughly.

Watering

Summer squash need to be watered throughout the growing season. Keep summer squash evenly moist and water deeply during dry spells. Water the bases of the summer squash plants to prevent mildew. Don't water the foliage. Watering summer squash in the early morning also helps prevent mildew. Summer squash also needs a lot of nutrients. Summer squash plants benefit from a monthly application of a complete organic fertilizer like fish emulsion or seaweed.

Harvesting

Summer squash are mature when they turn their mature color. Straightneck, crookneck, and zucchini summer squash are ideal when they reach 1-1/2" to 2" in diameter. Scallop summer squash are ideal at 3"-4" in diameter.

Harvest summer squash often. To avoid damaging the squash plant it is best to cut the summer squash from the vine rather than snapping it free.

Post-Harvest Handling

Wash and dry summer squash thoroughly. Avoid cuts and bruises when handling.

Storage

Summer squash held at 41°-50° and 90-95% relative humidity will last for 7-14 days.

Summer squash are sensitive to ethylene gas so do not store them with fruits and vegetables that produce ethylene gas.

Diseases

Anthracnose, Bacterial Wilt and Downy Mildew.

Pests

Squash Vine Borer, Squash Bugs and Cucumber Beetles.

Comments

Squash plants are very prolific. Plant only one or two plants for home use or you'll be swamped in squash.

References

Oregon State University, "Zucchini, Commercial Vegetable Production Guide", Last modified 2003-01-06, Oregon State University, http://www.oregonstate.edu/Dept/NWREC/zuc.html [1], Accessed 2003-05-21

Bradley, F. M. and Ellis, B. W.(Ed.). (1992), Rodale's All-New Encyclopedia of Organic Gardening: The Indispensable Resource for Every Gardener, Emmaus, Pennsylvania: Rodale Press.

Schultheis, Jonathan R., "Summer Squash Production", Last Modified 1993-09, Department of Horticultural Science, North Carolina Cooperative Extension Service, North Carolina State University, http://www.ces.ncsu.edu/depts/hort/hil/hil-24-a.html [2], Accessed 2003-08-02

Smith, E.C. (2000), The vegetable gardener's bible: discover Ed's high yield W-O-R-D system for all North American gardening regions., Storey Books: Pownal, VT.