Growing butternut squash (Cucurbita moschata) from seed, which is categorized as a winter squash, is similar to that of pumpkins, cantaloupe, and cucumbers who all reside in the same genus, Cucurbita. When to plant squash, like pumpkins, is dictated by the weather. This family of vegetables requires warm days. Planting butternut squash is most efficient when night temperatures are 60°F or above. Sow the seeds, ½ inch to 1 inch deep into well tilled and fertile soil. Since seedlings are prone to rotting if overwatered, it is best to soak the soil in which the seeds are to be planted and then not water the area again until the seedlings emerge. Butternut squash have a good resistance to the vine borer and cucumber beetles once they have grown beyond the seedling stage. If growing seedlings indoors, seeds should be planted in individual containers three to four week prior to the last frost date.
Butternut squash have a hard exterior which aids in their winter storage and can last up to a year. Winter squash should be harvested when the rind loses its shine, becomes dull and can no longer be dented by a fingernail. Leaving one inch of the stem on the squash will also help in storing. Keeping good ventilation and air temperature between 45°F and 60°F is ideal.
Growing Cucurbita Moschata
Winter squash such as butternut are seeded in the spring, grow through the summer, and are harvested and stored from fall through winter, which is how they earned their namesake. Butternut, as well as acorn and buttercup, are meant to ripen fully on the vine before they are picked. Good draining soil and full sun allow the plants to reach their full potential. Since squash vines can sprawl quite a bit, large areas or trellises are required. Light mulching may help reduce weeds, however, it may not be necessary as squash leaves are large and block light. Plant butternut squash 48 to 60 inches apart. If transplanting from seedling, an upturned pot placed over the seedlings for a few days can reduce the amount of wilting.
Seed Saving Tips
After growing butternut squash from seed, preserving the seeds from your harvest or even from a store-bought squash is easy. Scoop out seeds and separate from the pulp by picking through the seeds or placing them on a screen or colander, and gently hosing off the pulp. Dry the seeds on a paper towel or paper plate for a few weeks to ensure they are completely dry. Once dried, place in an airtight container (canning jar/freezer bag), and place in fridge or freezer. Seed germination will remain high for a couple of years. I store all of my seeds in the freezer. My neighbors have seeds that have been in air-tight bags for over 20 years and still maintain a germination rate of 80 percent.
Butternut squash, Cucurbita moschata, is closely related to other species of the squash family such as C. pepo, C. maxima, C. mixta. Hybrids can easily occur within a species and rarely between species. For example, the pumpkins Tan Cheese and Seminole and winter squash Pennsylvania Dutch Crookneck and Burpee’s Butterbush all are the same species (Cucurbita moschata) — they are just different varieties. To maintain pure butternut squash seeds it is recommended to isolate varieties by a minimum of 1/8 of a mile.
In the Kitchen
Butternut squash is easy to work with in the kitchen as it has a thin skin which is easy to remove with a vegetable peeler. Individual squash are small enough to be served to an average family without any leftovers. Although this squash is infamous for a creamy soup by the same name, it is very versatile. It can be roasted with eggplant and cabbage, baked with kale in a lasagna or served toasted on top of bread with ricotta cheese and balsamic vinegar.
Try These Varieties
- Autumn Glow
This butternut squash variety produces a stocky golden skin fruit averaging 8 inches. The flesh is tender and slightly sweet and nutty and is ready in 80 days. The plant is compact and does well in both container and traditional gardens.
Very vigorous and dependable. Fruits average 8-9 in. long, 3-4 lbs, and have buff-colored skin, and fine-textured, sweet, orange flesh. Can be harvested when small and used like a summer squash. Excellent resistance to vine borers. Stores very well.
Virginia grower Carl Kling has been growing Waltham butternut squash for many years, selecting for the longest keepers. One of the best performers in Twin Oaks Seeds’ 2012 butternut trials.
An Italian Butternut-type squash, these have a violin shape and wrinkled tan skin. The flesh is deep orange and sweet, perfect for desserts, roasting, stuffing, and baking. Good for marketing.
Do you enjoy growing butternut squash from seed? If so, what are your favorite varieties? Let us know in the comments below.