How to Grow Pumpkin and Squash
A tip sheet on how to grow and care for pumpkin and squash.
Pumpkin & Squash (Cucurbita pepo, Cucurbita maxima, Cucurbita moschata)
- Family: Cucurbitaceae (Cucurbits)
- Season: Warm
- Ease of growing: Medium
- Fertility needs: Medium
- Water needs: Medium
- Germination temperatures: 65°F to 100°F
- Germination time: 3 to 10 days
- Viability: 3 to 6 years
- Direct sow: late May to June
- Weeks to grow transplant: 3 to 4
- Start: late April to May
- Plant out: late May to June
- Typical spacing: 12” to 24” on 6’ rows
- Plants per square foot: 0.25 to .50
- Days to harvest: 50 to 125 from seed; 35 to 110 from transplants.
Squash varieties are classified as either summer or winter squash. Summer squash, including zucchini, is harvested when the fruit is immature. Winter squash is harvested after the fruit matures. Acorn, delicata and spaghetti squash are closely related to the summer squashes. Other winter squash, like butternut and buttercup, are botanically distinct. Pumpkins are grouped more by their size and use. There are giant pumpkins, pumpkins for pies and pumpkins for jack-o-lanterns.
Preparation and planting
Pumpkins and squash can be easily grown from seed. If transplanting, be careful to avoid disturbing the sensitive roots. Space summer squash and small-fruited winter squash closer together than large-fruited types.
Floating row covers provide beneficial extra heat early in the season and protect squash and pumpkins from striped-cucumber beetles. However, be sure to remove the row covers once plants have flowered to allow insect pollination. To avoid weed problems in winter squash and pumpkins, keep soil well-weeded until just before vining. Subsequent weeds will be smothered by dense vines.
Insects: Seedcorn maggots, striped cucumber beetles, cutworms, squash bugs, thrips, aphids, squash vine borers
Diseases: Damping-off, bacterial wilt, powdery mildew, gummy stem blight, black rot, alternaria leaf spot, anthracnose, angular leaf spot, phytopthora, several mosaic viruses
Harvesting and storage
The time from seed to harvest varies greatly within this group. The first fruits from summer squash, such as zucchini, should be ready by early July. If no disease problems develop and fruits are harvested regularly, plants will continue to produce until frost. Harvest summer squash young, they are best when 10 inches or shorter. Winter squash and pumpkins take much longer to mature. Start picking after the vines decline. Allow them to cure in the field for two to three weeks before storing.
Developed by James Manning, Undergraduate Research Assistant, and Daniel Brainard, Vegetable Extension Specialist; MSU Department of Horticulture; Gary Heilig, MSU Extension educator.