Winter squash is a name for several kinds of squash that are harvested when the fruit is fully grown and the skin has become hard. Winter squash is usually cooked before it is eaten. It can often be stored for weeks or months after harvest, unlike summer squash, which is picked young and has a soft skin.
The name "winter squash" does not mean that the plants grow in winter. The plants are warm-season crops. They are usually planted after the danger of frost has passed and harvested in late summer or autumn. The word "winter" refers to the way many types can be stored and eaten during winter.
Winter squash fruits usually have a hard rind, mature seeds, and dense flesh. The flesh may be orange, yellow, cream, or pale green, depending on the type. Many orange-fleshed winter squashes contain carotenoids, including beta-carotene, which the body can use to make vitamin A.
The plants often grow as long vines, although some varieties have a bush habit. Like other squashes, they have large leaves and yellow or orange flowers. The plants usually have separate male and female flowers on the same plant. Bees and other insects help pollinate the flowers.
Difference from summer squash
The main difference between winter squash and summer squash is the stage at which the fruit is harvested. Summer squash is picked while immature, when the skin and seeds are still soft. Winter squash is picked when mature, when the rind is hard and the seeds are fully developed.
Because of this, summer squash is usually eaten soon after picking. Winter squash can often be stored longer if it is harvested carefully and kept in a suitable place.
Types
Common types of winter squash include:
Acorn squash – usually small, ribbed, and acorn-shaped. It belongs to Cucurbita pepo.
Butternut squash – a tan squash with orange flesh. It belongs to Cucurbita moschata.
Buttercup squash – a dark green, round squash. It belongs to Cucurbita maxima.
Delicata squash – a small, long squash with pale skin and stripes. It belongs to Cucurbita pepo.
Hubbard squash – a large squash with a hard rind. It belongs to Cucurbita maxima.
Kabocha – a Japanese type of winter squash, often with green skin and dense orange flesh. It belongs to Cucurbita maxima.
Pumpkin – a common name for several round or nearly round winter squashes, often orange.
Spaghetti squash – a squash whose cooked flesh separates into strands. It belongs to Cucurbita pepo.
Turban squash – an ornamental and edible winter squash with a rounded "turban" shape.
Pumpkins and winter squash
The word pumpkin is used in different ways in different countries. In North American English, "pumpkin" often means a round orange squash, especially one used for food, decoration, or Halloween. In Australian and New Zealand English, "pumpkin" can mean many kinds of winter squash, including types called squash in North America.
There is no single botanical difference that separates all pumpkins from all other winter squashes. Pumpkins may belong to several Cucurbita species, including C. pepo, C. maxima, and C. moschata.
Harvest and storage
Winter squash should usually be harvested when the rind is hard and the fruit has reached its mature colour. Many growers leave a short piece of stem attached to the fruit, because fruit without a stem may rot more easily. The fruit should be handled carefully, because cuts and bruises can shorten storage life.
Some types are cured after harvest. Curing means keeping the squash in a warm place for a short time so the rind can harden and small wounds can heal. Storage time depends on the type of squash, how mature it was at harvest, and the storage conditions.
Food use
Winter squash is usually cooked before eating. It can be roasted, baked, steamed, boiled, mashed, or used in soups, stews, pies, breads, and other foods. Some types, such as delicata and some kabocha, may have edible skin when cooked, but many types have skin that is too tough to eat.
The seeds can also be eaten. They are often cleaned, roasted, and salted. Squash blossoms are edible too, but they are more often associated with summer squash or with squash plants grown for flowers.
Nutrition
Winter squash is mostly water and carbohydrate, with small amounts of protein and fat. Orange-fleshed types are known for carotenoids such as beta-carotene. Winter squash can also provide fibre, potassium, and vitamin C, although the exact amount depends on the species and variety.
