How to Grow BUTTERNUT SQUASH
Summer squash comes in a variety of shapes and colors. Bush varieties take up relatively little space, and if kept picked will keep producing right up to frost.
Winter squash are easy to grow -- if you have room. In addition to the familiar butternut and acorn squash, varieties come in a staggering diversity of fruit size, shape and color. Choose bush varieties if space is tight.
Seeds or Seedlings
5 to 10 days, 60F to 105F
Well Drained, High Fertility
4" to 12 " apart
18" to 36 " apart
DAYS OF HARVEST
50 to 60
Squash like warm soil and are very sensitive to frost. So don’t be in a rush to plant early in spring. Wait until danger of frost has passed and soil has warmed to about 70 F, or about 2 weeks after the last frost date.
Unless you are trying to grow a long-season variety in an area that gets early frosts, there’s really no need to start winter squash inside. Instead, direct seed ½ to 1 inch deep into hills (which warm and drain earlier in the season) or rows. Sow 4 to 5 seeds per hill. Space hills about 4 to 8 feet apart, depending on the size of the fruit. (The larger the expected size of the squash, the larger the vine and the farther apart you should space the hills.) When the plants are 2 to 3 inches tall, thin to 2 to 3 plants per hill by snipping off unwanted plants without disturbing the roots of the remaining ones. In rows, sow seeds 6 to 12 inches apart in rows 4 to 8 feet apart. Snip off plants to thin to one plant every 18 to 36 inches.
To hasten first harvest by as much as 2 weeks, use black plastic mulch to warm soil before direct seeding or transplanting. Early fruits are sometimes wrinkled, turn black or rot due to poor pollination.
At the end of the season, remove or till in vines to reduce mildew. Use row covers to protect plants early in the season and to prevent insect problems. Remove cover before flowering to allow pollination by insects or when hot weather arrives.
Summer - 60-70 days. These squash are picked immature before they are fully formed. The skin should be soft and tender, otherwise the squash will be overripe and of poor quality.
Check squash plants almost daily when they start to flower, as the fruit will develop in 2 or 3 days in hot growing weather. The vines must be kept picked or the plants will stop producing.
Winter - 90-120 days. When the stems turn a light green yellow color, the squash should be fully ripe. The rind will be thick and tough. Cut, do not pull, the ripe fruit from the plant. Two to three inches of stem must remain for proper storing. This may increase the sugar content.
Insect pollinated. Take caution unless you are hand pollinating, as many summer squash varieties are the same species as many pumpkins and winter squashes. Different varieties of the same species need to be isolated by 1/4 mile to prevent cross-pollination. Barriers such as tree lines, woods or buildings existing between the fields can reduce this distance. Treat summer squash the same as usually done for winter storage of squashes and pumpkins, allowing summer squash varieties to grow to a large size with a hard outside skin. After all squashes have reached this stage, harvest and let them sit for a period of after-ripening for 3-6 weeks or up to several months. Remove the seeds, rinse in water and dry. Use of a 1/2" and 1/4" screen can help with cleaning. Squash seeds remain viable for 6 years under cool and dry storage conditions.
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