Squash, Winter Growing Guide

Also known as Butternut squash, Acorn squash. Winter squash are easy to grow if you have room. In addition to the familiar butternut and acorn squash, varieties
come in a staggering diversity of fruit size, shape and color. Choose bush varieties if space is tight.

Site Characteristics

 full sun
Soil conditions:
 requires well-drained soil and high fertility
 Prefers well-drained, fertile, loose soil, high in organic matter with pH between 5.8 and 6.8. Plentiful and consistent moisture is needed from the time plants emerge until fruits begin to fill out.

Plant Traits

Lifecycle: annual; tender annual
Ease-of-care: easy
Height: 1.5 to 3 feet
Spread: 3 to 15 feet; most varieties grow on vines that spread 6 feet or more. If space is tight, choose smaller bush or semi-bush varieties.
Bloom time:
 mid-summer
 late summer
Flower color: yellow
Foliage color: medium green
Foliage texture: coarse
 low and trailing
 climbing / vine
Shape in flower: same as above

Growing Information

How to plant:
 Propagate by seed—seed can be saved 6 years
 Germination temperature: 60 F to 105 F—will not germinate in cold soil. Wait to plant until soil reaches at least 65 F—preferably 70 F or more. Germinates best at 95 F.
 Days to emergence: 5 to 10—should germinate in less than a week with soil temperature of 70 F and adequate moisture.

Maintenance and care

Squash like warm soil and are very sensitive to frost so don’t be in a rush to plant early in spring. Wait until danger of frost has passed and soil has warmed to about 70 F or about 2 weeks after the last frost date.

Unless you are trying to grow a long-season variety in an area that gets early frosts, there’s really no need to start winter squash inside. Instead, direct seed ½ to 1 inch deep into hills (which warm and drain earlier in the season) or rows. Sow 4 to 5 seeds per hill. Space hills about 4 to 8 feet apart, depending on the size of the fruit. (The larger the expected size of the squash, the larger the vine and the farther apart you should space the hills.) When the plants are 2 to 3 inches tall, thin to 2 to 3 plants per hill by snipping off unwanted plants without disturbing the roots of the remaining ones. In rows, sow seeds 6 to 12 inches apart in
rows 4 to 8 feet apart. Snip off plants to thin to one plant every 18 to 36 inches.

If you need to start plants early, plant inside in 2- to 3-inch pots or cells 3 to 4 weeks before transplanting outside. Sow 3 or 4 seeds per pot and thin to one or two plants by snipping off the weaker plants to avoid damaging the roots of those that remain. Harden off by cutting back on water and reducing temperature before transplanting. Plant transplants out in the garden at the same final spacings listed above after all danger of frost has passed.

Black plastic mulch can speed growth especially in cool, short-season areas. At the end of the season, remove or till in vines to reduce mildew. Use row covers to protect plants early in the season and to prevent insect problems. Remove before flowering to allow pollination by insects or when hot weather arrives. Mulching plants helps retain moisture and suppress weeds. Mounding soil around the base of the plants can discourage squash borers from laying eggs.


Squash bug—hand pick. Bury or compost plant residues after harvest.
Squash vine borer—remove by hand. Butternut squash is resistant.
Striped cucumber beetles—construct tents of fine netting or cheesecloth or use floating row cover over young plants. Put in place at planting and remove before flowering. Control of beetles may be a factor in preventing bacterial wilt.


Bacterial wilt (Erwinia tracheiphila)—remove and destroy infested plants. Control cucumber beetles if they appear.
Powdery mildew—avoid wetting foliage if possible. Water early in the day so aboveground plant parts will dry as quickly as possible. Avoid crowding plants. Space apart and eliminate weeds around plants and garden area to improve air circulation.
Scab—avoid wetting foliage if possible. Water early in the day so aboveground parts can dry as quickly as possible. Avoid crowding plants, Space apart and eliminate weeds around plants and garden area to improve air circulation. In autumn, rake and dispose of all diseased leaves and fruit. Do not save your own seed.
Viral disease—remove and destroy entire infested plant along with immediately surrounding soil and soil clinging to roots. Eliminate wild cucumber and milkweed nearby. Control aphids early in the season.

Other diseases:
Downy mildew


Whether they are Cucurbita pepo (the same species as summer squash) C. moschata, or C. maxima, most varieties of winter squash produce sprawling vines. If space is tight, grow bush or semi-bush varieties.

Winter squash
come in a staggering array of sizes, shapes and colors. If your season is short, avoid varieties that require a long growing season (100 or more days).