A ripe butternut squash will be heavy for its size, which means it's got a high water content and is ready to eat. So, go ahead and pick up a few squashes, and see which one feels like it's got some heft to it - that's the one you want! It's like choosing the perfect melon - you want it to feel substantial, not light and hollow.
5 Signs Your Butternut Squash are Ready for Harvest - The Seasonal
Now, you might be wondering what happens if you accidentally pick an unripe squash. Don't worry, it's not the end of the world! You can actually ripen it at home by leaving it at room temperature for a few days. Just be patient, and it'll eventually sweeten up and be ready to use. After all, good things come to those who wait, right?