Cucurbita maxima – Winter Squash

Cucurbita maxima is a winter squash in the Cucurbitaceae plant family, alongside melons, spaghetti squash, and cucumbers.

The most popular varieties of squash belong to one of these three species: Cucurbita pepo, C. moschata, and C. maxima.

What is Winter Squash?

• Although often considered a vegetable, it is botanically classified as a fruit, as it grows from a flowering plant and contains seeds.
• Native to subtropical areas of South America (Argentina-Bolivia-Uruguay), Cucurbita maxima is a long-vining plant, although some bush cultivars are now available.
• It produces pale to deep flowers during the summer that give way to fruits maturing in late summer to fall.
• The fruits come in a huge range of shapes (rounded to cylindrical), colors (from blue to gray, pale green, orange or multi-colored), and skin textures.
• Among them are pumpkin (some incredibly large), buttercup, hubbard, turban, banana, and Australian blue varieties.
• Many of these winter squashes are prized for their excellent flavor.
• Leaves, flowers, pulp, and seeds are edible.
• Winter Squash is a warm-season crop and can easily be injured by frost.
• It is best suited for large landscapes but performs well in vegetable gardens and on trellises.

Health Benefits of Winter Squash

• While Winter Squash is a flavorful addition to savory dishes, it also provides health benefits.
• Winter Squash is low in calories (90% water) but is rich in vitamins, minerals, and antioxidants.
• Beta carotene is a powerful antioxidant that gives fruits and vegetables their orange color. It is partially converted into vitamin A by the body.
• Vitamin A: one cup of Winter Squash provides 214% of your daily needs. This vitamin is essential for your eyes, immune system, heart, and kidneys.
• Vitamin C: one cup provides 33% of your daily needs. Vitamin C strengthens the immune system.
• Potassium: one cup provides 14% of your daily needs. Potassium helps regulate fluid balance, nerve signals, and muscle contractions.
• Iron: one cup provides 5% of your daily needs. Iron is essential for growth and development and improves mental and physical performance.
• Fiber: one cup provides 23% of your daily needs. Fiber slows sugar absorption into the blood, promotes regular bowel movements, smooths digestion, and can also help reduce the risk of colon cancer.
• Fiber, potassium, and vitamin C in Winter Squash support heart health and may also reduce the risk of cardiovascular diseases.
• Beta carotene, and vitamins C and E are also important for your skin health.
• Nutrition Facts (one cup): 76 calories, 18 grams of carbs, 1.8 grams of protein, 0.7 grams of fat, and 5.7 grams of fiber.

Cooking with Winter Squash

• When cooked, Winter Squash is tender and offers a mild, sweet taste with nutty flavors, depending on the varieties.
• Winter Squash is best suited for baking, boiling, steaming, and roasting.
• Its versatile flavor makes it part of spicy, sweet, or savory dishes.
• Winter Squash is popular in pancakes, pies, custards, and muffins.
• It can be used to prepare thick, creamy soups or seasoned with salt and pepper and roasted in the oven.
• The seeds are also edible and can be eaten as a snack when toasted.
• The flowers have a soft, delicate texture and can be stuffed with soft cheeses and herbs, then battered and fried.
• Uncut Winter Squash can be stored for up to 6 months in a cool and dry place. Once cut, it should be used within one week.

Growing Winter Squash

• Winter Squash grows up to 10-18 in tall (25-45 cm) and 10-12 ft long (400-360 cm), depending on the variety.
• It performs best in rich, fertile, acidic to neutral (pH ranging from 6 and 6.8), moist, well-drained soils in full sun (at least 6-8 hours of direct sunlight per day) in a sheltered location.
• If your soil lacks nutrients, add well-rotted organic matter or compost before planting.
• Keep the soil evenly moist but not soggy. Regulate irrigation properly to avoid excessive moisture or water stress.
• Do not splash the leaves when you water the plant. Prevent disease problems by keeping them dry.
• Depending on the variety, Winter Squash takes 75-100 days to harvest after planting.
• Winter Squash is usually direct-seeded when all danger of frost has passed and the soil temperature is at least 65-95°F (18-35°C).
• If your growing season is short, start seeds indoors about three weeks before the last spring frost date. Please note that Squash seedlings do not always transplant well.
• Planting in rows: Sow seeds 1 inch deep (2.5 cm) and 24-36 inches apart (60-90 cm) in rows that are 3-6 feet apart (90-180 cm).
• Planting in hills (raised mound of soil): Sow 3 or 4 seeds in hills that are 3-6 feet apart (90-180 cm).
• Planting in hills benefits: Hills enable the soil to warm faster early in the season, provide better drainage, and allow for increased pollination (since several seeds are planted together).
• Water thoroughly after planting.
• Cover plants with a floating row cover in order to protect them from insects and late cold snaps.
• Remove the row cover when the plants begin to flower so insects can pollinate the flowers, or you will not get any fruit.
• Mulch to retain moisture, keep the soil warm, and control weeds.
• Fertilize every 10–14 days with a high-potassium liquid fertilizer, such as tomato feed, once the first fruits start to swell.
• To grow bigger Winter Squash, pinch the vines back once the fruits appear so the energy goes into the fruit.
• Rotate crops: Prevent problems by not planting any member of the cucurbit family (cucumbers, melons, and squash) in the same place more often than every four years.
• Winter Squash is susceptible to a few pests. Keep an eye out for aphids, cucumber beetles, squash bugs, squash vine borers, slugs, and snails.
• Winter Squash is susceptible to diseases, including anthracnose, cucumber mosaic virus, downy mildew, gray mold or botrytis, and powdery mildew.

Plant Hand Pollination

• Winter Squash plants produce male and female flowers. However, only pollinated female flowers produce fruit.
• Bees are the primary pollinators of squash plants, although other flying insects can be pollinators.
• In case of poor pollination because of weather conditions or a lack of pollinators, you can try to hand-pollinate your plants yourself.
• Remove a male flower (no swelling at its base) and brush the central parts against the center of a female flower (female flowers have a tiny fruit at the base).
• If the female flower is pollinated, the flower shrivels and closes, and a tiny squash fruit grows into a full-size fruit.
• If there is no pollination, the tiny fruit shrivels and drops from the plant.

Harvesting and Storing

• Winter Squash requires a long growing season to allow the fruit to produce and ripen.
• Do not harvest the squash until after the vines have died but make sure you harvest them before freezing temperatures hit.
• The skin of a ripening squash should be hard, with a uniform color, and should not dent when pressed with a fingernail.
• Carefully cut fruits off the plant with pruners or a knife.
• The flowers can also be harvested and have a slightly sweet flavor. They can be stuffed and fried or eaten raw in salads.
• To help squash plants to store longer, harvest with a few inches of stem still attached.
• Handle Winter Squash very gently, or it may bruise. Never carry your squash by its stem.
• Winter squash must be cured before storage. Curing helps to harden the squash skins and heal any cuts and scratches.
• After harvesting, cure for 7-14 days at a temperature of 80-85°F (26-29°C) and relative humidity of 80 to 85%.
• After curing, they can be stored in a dry and reasonably cool area, 50-55°F (10-13°C) for 4-6 months. High humidity and extreme temperatures will damage Winter Squash quickly.

Best Companion Plants

A good example of companion planting is The Three Sisters Garden. Practiced by Native Americans thousands of years ago, this garden includes corn, beans, and squash. The tall corn provides shade for the lower squash but also stops the squash vine borer beetle. Corn also provides support for the bean plants to climb up. The beans enrich the soil with nutrients for both corn and squash. And the large leaves of the squash vines create a protective mulch that helps retain moisture while suppressing weeds. Another added benefit is the prickly vines of the squash deter the raccoons from stripping the corn cobs.

• Beans fix nitrogen and add nutrients that improve the soil, benefitting the plants that are growing beside them.
• Borage flowers attract beneficial insects and help deter pests from your plants. Borage also enriches the soil and improves the growth and flavor of squash plants. As a bonus, the flowers are edible.
• Buckwheat attracts spiders and ground beetles, keeping them away from the squash plants.
• Catnip is good for deterring ants, weevils, squash bugs, Japanese beetles, flea beetles, and mice.
• Corn provides shade and stops the squash vine borer beetle.
• Dill flowers attract beneficial insects such as hoverflies and ladybugs (prey on aphids) and predatory wasps (prey on caterpillars and other insects), which help keep pest levels down.
• Chamomile attracts hoverflies and wasps, repels Mexican bean beetles, and accumulates calcium, potassium, and sulfur, later returning them to the soil. Growing chamomile is considered a tonic for anything you grow in the garden.
• Legumes such as peas help your squash plants receive enough nutrients by fixing the nitrogen and increasing the nutrients in the soil.
• Lemon balm also repels squash bugs, which makes it a good companion plant for squash and pumpkin plants.
• Lovage improves the flavor and vigor of most plants and offers a good habitat for ground beetles.
• Marigolds help deter beetles.
• Marjoram is a friend to all plants and helps improve growth and flavor.
• Nasturtium is known to deter whiteflies, wooly aphids, squash bugs, cucumber beetles, and other pests.
• Oregano provides general pest protection. It attracts hoverflies and Syrphidae and repels aphids.
• Radish is thought to protect all squash family members from squash borers and flea beetles.
• Spinach: It’s a good use of space because, by the time squash plants start to get big, the spinach is ready to bolt.
• Sunflowers grow tall and provide helpful shade for squash plants in hot summer areas.
• Tansy helps concentrate potassium in the soil, benefiting nearby plants. It also repels cutworms, cabbage worms, squash bugs, striped cucumber beetles, Japanese beetles, ants, flies, mosquitoes, and fruit moths.

Worst Companion Plants

Avoid planting these vegetables in your home garden nearby your squash plants.

• Fennel: Most plants dislike fennel, which has an inhibiting effect on them.
• Potatoes: These root vegetables can deplete the soil of nutrients and starve your squash plants nearby.
• Sweet potatoes will compete with squash plants for space: these vigorous growers like to spread out.