How to Grow Butternut squash

Soil is the first consideration when growing vegetables. It is always a good idea to start with having your soil tested. The University of Minnesota has a testing service than can be accessed here. For best yield and quality, the soil pH range for vine crops is between 6.0 and 6.5, which is slightly acidic. Raised beds are recommended as they ensure good drainage. You can seed vine crops directly into the garden, but they need warm soils of about 65°tested at 2” down. Follow directions on the butternut squash seed package for seed depth and row spacing.

To start your butternut squash inside, plant seeds in pots or cells at least two inches wide and deep. Seedlings take about four weeks from seeding to planting out. They need two to three true leaves before transplanting. Harden off seedlings started indoors before planting them in soil that is at least 65°F  Read more about starting seeds indoors at this University of Minnesota Extension website. 

Now that your squash is in the ground, they need at least one inch of water each week. Trellised plants may require watering more often. Water deeply by using a drip hose, soaker hose or careful watering of the soil making sure to keep the leaves dry. 

Poor fruit set and tasteless fruit can be due to rainy, cloudy or cold weather, when pollinators are not active. Heavy rainfalls can lead to oedema, which causes scabby, raised bumps on the fruit. 

If you want to use mulch, such as straw or compost to control weeds, wait until the soil is at least 75°F because the mulch can inhibit further warming.  When the vines start to spread out, side dress with high-nitrogen fertilizer. Consult your soil test for amounts.

The first blossoms often drop from the vines. This is not a problem, since the first blossoms are male, the female flowers, which open later, have a swelling at the base called the ovary. After pollination, the fruit develops. 

After your butternut squash is ripe, pick it before a hard freeze for best results. A light frost that kills the vine will usually not harm the fruit. Cut the fruit from the vine, leaving a few inches of stem attached. Be careful not to cut or bruise the fruit. After cutting squash from the vines, you should “field-cure” them in place for a week or two in dry, sunny weather. This dries and toughens the skin for longer storage. If the weather becomes cold or rainy, cure the squash indoors in a well-ventilated, warm (80°F) place.

Storage

Winter squash should be stored in a cool (55°F) place, with good air movement. If you don’t have a good place to store them, you can freeze mashed squash, dry slices in a dehydrator, or can it. Check this site for more information about preserving winter squash. 

Butternut squash can be made into many dishes, from soups to roasted or candied cubes. Check out our Garden to Kitchen article this month for a mouth-watering squash recipe.

Bon appétit!

Photo and Drawing Credits: Marjory Blare (1,2,3)