The butternut squash is a winter squash. Allow a winter squash to fully mature on the vine until the skins are very hard. When ready to harvest, they should be cut from the vine, leaving several inches of vine stem on each squash. The extra thick skin of the winter squash allows them to be stored for a longer period than a thinner-skinned summer squash.
Count 110 days after sowing and mark that date on your calendar. This will give you an approximate date range to begin checking your butternut squash for harvesting.
Observe the squash as they mature. Periodically visit the garden and acquaint yourself with the appearance of the squash. To recognize the changes in a ripe squash, you will need to know what they looked like in the unripe stage.
Note the color changes of the butternut squash. When ripe, the skin will change from light beige to deep tan.
Tap the rind gently. When ready to harvest, the butternut squash’s rind will be much harder than an under-ripe squash.