Butternut squash is a sweet winter squash, related to pumpkins and acorn squash, that spreads its vines and broad leaves out in summer and stores sunny energy and antioxidants in its deep orange, late-summer fruit. Like all the winter squashes, it can shade the roots of taller companion plants (such as in a “Three Sisters” garden). The flowers, seeds, and even the leaves are edible, though most people only use the squash itself in a creamy soup, risotto, or butternut ravioli or gnocchi, or as a boiled-and-mashed side dish.
When planting butternut squash, choose a site where no powdery mildew or cucumber beetle infestations have occurred recently. It is also best to plant winter squashes away from plants that attract the same pests, such as cucumbers and melons. Like most of the vining cucurbits, butternut squash needs some space. You can, however, trellis them, if horizontal space is limited. Good air circulation around plants helps them ward off diseases.
Though it is possible to start seeds in trays if your growing season is short, squash seeds are usually planted directly after soil warms up to about 60 degrees F. Shape soil into mounds about four feet apart, and plant two seeds in each, about an inch deep. If you plant more seeds, you will have to thin them. A University of Oregon study found that increased plant density may result in a larger overall number of smaller fruits, so adjust accordingly for your size preference.l