How to Grow & Care for Butternut Squash

Butternut squash (Cucurbita moschata) is a type of winter squash. The plants are annuals that grow in almost any climate. They are planted in spring, following the last frost of the season. Their vines grow quickly, but the fruits may not be ready to harvest for three to four months from planting time. For smaller space gardens, bush varieties of butternut squash are also available. The plant requires full sun and slightly acidic to neutral soil. Read on for our growing guide.

Botanical Name	Cucurbita moschata
Common Names	Butternut squash, Butternut pumpkin, Gramma
Plant Type	Annual
Mature Size	9-18 in. tall, 10-15 ft. wide (vine length); bush varieties take up less space
Sun Exposure	Full sun
Soil Type	Rich, well-drained
Soil pH	Acidic to neutral (5.5 to 7.0)
Bloom Time	Summer
Flower Color	Yellow
Hardiness Zones	2 to 11 (UDSA)
Native Area	Central America, South America

Butternut Squash Care

These are the main care requirements for growing butternut squash:

• Needs full sun
• Soil should be well-draining
• Apply liquid fertilizer or compost tea every 2-3 weeks
• Requires one inch of water per week

Light

Butternut squash needs full sun, ideally 6 hours per day. More time in the sun is fine, provided the plants are not overheated.

Soil

The soil should be rich in organic material, and it must drain well. It can be slightly acidic to neutral, with a pH of 5.5 to 7.0.

Water

Seedlings must not be allowed to dry out. As the summer progresses and the vines get bigger, your plants will need even more water. During hot, dry weather, leaves may wilt on a daily basis but will revive as the day cools. If leaves are wilted in the morning, water the plants right away. The plants need at least 1 inch of water per week.

Fertilizer

Butternut squash is a heavy feeder. Start with rich soil, and side dress with organic compost or aged manure in the middle of the growing season. In addition, apply a compost tea or liquid fertilizer at two- to three-week intervals.

Temperature and Humidity

Squash are cold-sensitive and will not germinate unless the soil is at least 70 degrees Fahrenheit. These plants love the sun, but they can overheat. During the hot days of summer, it's normal for the leaves to wilt in the afternoon, then revive after the sun goes down. If your plants are not reviving, try giving them some afternoon shade.

Types of Winter Squash

A "winter squash" is defined as a kind of squash that has a hard enough skin that it preserves well if stored in a cool place. Thus, if you were to harvest one in October, it would keep until at least December (winter) if stored in a suitable place, such as un unheated basement or root cellar.

Butternut squash is just one of several winter squashes that are commonly grown. Another popular winter squash is Hubbard squash (Cucurbita maxima), which has a gray, bumpy exterior.

In contrast to winter squashes, there are also summer squashes, such as zucchini squash (Cucurbita pepovar.cylindrica). Summer squashes have a soft skin that is edible and perish quickly.

How to Grow Butternut Squash From Seed

Most gardeners purchase butternut squash seed packets (available at grocery stores, hardware stores, online, and from seed catalogs). Once you have the seeds, you can start them indoors to get a jump on the season, or you can wait until danger of frost has passed and direct-sow outdoors. Direct seeding in the garden is easier, but starting seeds indoors can be helpful to those in areas with short summers.

1. To start seeds indoors, plant them about three weeks before the last frost in spring.
2. Fill 3-inch biodegradable pots with potting soil, and plant two seeds in each pot. Water, and place the pots in a sunny window. Do not let the soil dry out completely.
3. If both seeds in a pot germinate, select the healthiest seedling as the one to keep and pinch out the other.
4. When the plant has two sets of true leaves, begin the hardening off process. On warm days, set the pots outdoors in partial sun for a few hours at a time. Bring them back indoors at night. Gradually increase the number of hours that they stay out, as well as the sun exposure. This process helps them adjust to the transition from an indoor environment to an outdoor environment.
5. Plant the biodegradable pots in the ground once the soil temperature is at least 65 degrees Fahrenheit and all threat of frost has passed.
6. If you choose to direct seed, simply skip to the step where you create hills and plant four or five seeds in each hill, thinning them out later.

Common Pests & Plant Diseases

Butternut squash can be susceptible to squash bugs, which can cause leaves or whole vines to turn brown, wilt, and/or eventually die. These bugs are most active from late summer to winter. To combat, you should remove any infected plants to prevent spread to the others. You can also try spray with a mixture or warm soapy water (using dish soap). Note that there are varieties of butternut squash that are resistant to these bugs that you can choose to plant, such as 'Royal Acorn' and 'Sweet Cheese'.

When the seedlings are young, they are susceptible to drought (so keep their soil moist) and to damage from slugs and snails. Be sure to take control measures against these pests. Later in the season, Japanese beetles can become a problem. Pick them off by hand and throw the beetles in a bucket of soapy water.

Butternut squash can fall victim to powdery mildew, a fungal diseases that affects squash plants. Affected plants will see the mildew cover leaves, which will then turn yellow or brown, curl up, and die. To combat, plant disease-resistant varieties, plant in full sun, and adhere to proper spacing when planting.

Common Growing Issues

Yellow, Drooping Leaves

Yellow and/or drooping leaves can be indicative of an overwatered butternut squash plant. Test the soil, and if it feels overly wet or soggy, pull back on watering until the plant recovers and a moisture-balance is restored.

Fruit Falling Off

Butternut squash fruit can fall off the plant if the growing conditions are not met (perhaps not enough sun or too little or too much fertilizer) or if there is poor pollination. Make sure your squash is planted near a pollinator plant.

From: thespruce