How to Plant and Grow Winter Squash

Winter squashes (Cucurbita spp.) are known for their hard skin, which protects the gourds through the fall, winter, and sometimes spring, depending on the variety. Winter squash requires a long growing season, but little maintenance (beyond regular watering) between planting and harvesting. They require more time, space, and attention than summer squash, but are well worth the effort and wait.

There are dozens of varieties of winter squash—all of which (including pumpkin) feature edible flesh. Of course, the amount of available flesh varies by type, as does the flavor and texture. So, if you love roasted squash or homemade pumpkin pie, you are just 60 to 100 days away from making those dishes with winter squash that you grew yourself.

Where to Plant Winter Squash

Winter squash plants need lots of space to grow. Most require at least 4 to 6 feet to spread out, but some pumpkins can sprawl up to 15 feet. They’ll take over a garden quickly if not provided with plenty of room. If you lack space, grow small-fruited winter squash vertically on a sturdy trellis or opt for a bush-like cultivar. Large squash is too heavy to trellis.

All types of squash require six to eight hours of full sun each day and rich, well-draining garden soil.

How and When to Plant Winter Squash

The best way to grow winter squash is from seed, and you don’t need to start them indoors like some vegetables. These seeds need warm soil, so you should wait at least two to three weeks after the last frost date in your area to sow the seeds. If you put the seeds in the ground too early, they will rot.

To plant your seeds, make hills of soil about 1 foot in diameter. Mound them up a few inches to improve drainage and give the seeds an abundance of good soil to grow in. Leave plenty of room—5 to 6 feet—between hills unless you are planting a bush variety squash. When the ambient temperature reaches 65°F, put four to six seeds in a hill and cover them with 1 inch of soil. They need warmth to germinate.

As the plants emerge, thin out every other seedling until you have two or three plants on one hill. As plants grow and sprawl, use a straw mulch underneath your pumpkins and squash to prevent them from being discolored or disfigured from sitting on the ground.

Winter Squash Care Tips

Light

Winter squash plants require six to eight hours of direct sunlight daily.

Soil and Water

Winter squash plants grow best in rich, well-draining soil with a pH range of 6.0-6.5. Test your soil’s pH and amend it if necessary to reach this range.

Once the plants fill out, they take a fair amount of water, so a consistent watering plan is crucial. Winter squash need at least 1 inch of water weekly from rainfall or irrigation. Water the plants at the soil level and keep the leaves and fruit as dry as possible to minimize plant diseases. A drip hose or soaker hose is handy for this purpose. Reduce watering as your winter squashes ripen to avoid rot.

Temperature and Humidity

Most winter squash prefer warm weather and grow best in 50°F to 90°F. Winter squash plants tolerate light frost for short periods. A light frost that kills the squash vine might not kill the fruit; it can be harvested if ripe and undamaged. If colder temperatures are forecast, protect the plants from frost with tarps or blankets.

Squash plants tolerate a wide range of humidity levels as long as they receive water regularly.

Fertilizer

If your soil is enriched with compost at planting time, supplemental fertilizer may not be needed. If you don’t have compost, work three to four pounds of a 10-10-10 fertilizer into every 100 square feet of garden space before planting.

Many gardeners also recommend an application of organic liquid fertilizer when the plants start to bloom and again a month later, following the product directions.

Pruning

Pruning is not required, but cutting back a few non-producing vines at their base may improve the size of the developing fruit on the remaining vines.

Potting and Repotting

A single squash plant can grow comfortably outdoors in a 5-gallon container filled with well-draining potting mix (not heavier garden soil) as long as all its other needs are met—especially the sun and water requirements. A bush variety is a better fit for a container than a vining type of squash, although both are possible.

Winter squash plants do not take well to transplanting, so be sure to select a container large enough to accommodate the plant's mature size.

Pests and Problems

Pumpkins and squash have several pests that can plague them. Keep a close eye on your squash, and when you see yellowing leaves or holes, do a little investigating.

The main pests that afflict winter squash are cucumber beetles. These are easy to control if there are a few here and there, but a heavy infestation can devastate your crop.

Since winter squash is edible, look for natural solutions to control pests. The easiest and most effective way to rid your patch of beetles is to manually pick them off as you see them. Garden centers also sell different types of traps—the most common being a sticky trap to put in your plot.

If your garden is prone to issues, look for squash varieties that are more disease- and pest-resistant to minimize problems.

How to Propagate Winter Squash

The easiest way to propagate winter squash is via cuttings or by collecting seeds. Just be aware that the resulting fruit may not be exactly like the parent plants' fruit. Winter squash tends to cross-pollinate with other squashes and pumpkins.

If you aren’t concerned with cross-pollination, cut open any mature fruit and remove the seeds. Wash the pulp from the seeds and spread them across a paper towel to dry. Place the towel with the seeds in a dry area away from direct sunlight. After a week, store the dry seeds in an envelope. Label them and keep the seeds in a cool, dry place until you are ready to sow them.

Winter squash can also be propagated by taking stem cuttings from healthy plants. Each cutting should contain at least two or three nodes. Insert your cuttings into pots filled with well-draining potting mix and put them in a warm, bright light location (not direct sun). Keep them well watered, and the stem cuttings should begin to form roots in a couple of weeks. When your plants have rooted, move them to the garden after a week of hardening off. This process is usually used only with short-season squash.

Harvesting Winter Squash

When pumpkins and other types of winter squash reach the size you expect them to be, it’s harvest time. Look for fruits that don’t have blemishes or cuts. The skin should feel firm (not mushy), and the fruit should feel heavy for its size due to the abundance of moisture inside. Make sure to cut off the stem when harvesting—don’t tear it. Store pumpkins and squash in a cool, dry place so they won’t rot.

Types of Winter Squash

Pumpkin

Pumpkins (Cucurbita pepo) are grown in nearly all zones (2-11) and come in lots of varieties from mini to giant. Most have been bred to be decorative, but some are meant for eating. Plus their seeds are edible. The vines may reach 15 feet in length.

Butternut Squash

With butternut squash (Cucurbita moschata ‘Butternut’), the name says it all—you don’t need to add butter. Butternut squash has tan-colored skin and orange-yellow, sweet flesh. As an annual, it thrives during warm weather in zones 2-11.

Spaghetti Squash

Spaghetti squash (Cucurbita pepo) has a unique texture. It is a reliable crop in zones 2-11 and develops on 8 foot vines with large, heart-shape leaves. Its yellow flesh creates noodle-like strands that are a tasty low-carb alternative to pasta.

Delicata Squash

The skin of delicata squash (Cucurbita pepo ‘Delicata’) is thin and tender enough to eat after cooking, which sets it apart from other winter squash varieties. Its small size makes it an ideal candidate for slicing or stuffing with a filling of your choice.

Acorn Squash

Acorn squash thrive in zones 3-11 but fare best in mild climates. These ridged, acorn-shape gourds feature dark green skin with patches of orange and yellow as well as sweet, yellow-orange flesh.

Winter Squash Companion Plants

Corn

Corn is one part of the traditional plant partnership known as the Three Sisters (squash, beans, and corn). Corn is often grown with winter squash because the vines cover the soil to keep down weeds and retain soil moisture. Meanwhile, the corn stalks provide a sturdy support for beans (another of the sisters) to grow on.

Beans

Pole beans are nitrogen-fixing plants that improve the soil for both squash and corn. The beans benefit by using the corn as a support for climbing. They are easy to grow from seed sown directly in the garden.

Dill

Aromatic dill repels squash bugs and other insects, so it is a welcome addition to a garden plot with winter squash. It’s also a favorite food for black swallowtail caterpillars, and its small yellow flowers are excellent for attracting a variety of pollinators.