I keep my winter squash in a wooden crate that Countryboy built for me. I line it with clean straw and place the squash between more layers of straw. This works like a charm.
Do this, and you can enjoy butternut squash for months. (Some other winter squash, like Delicata, also last a long time when stored like this.)
But nothing lasts forever. By March I usually see a few dark spots on any remaining squash. At this time I roast the squash in the oven, scoop out that pretty orange flesh into plastic bags and freeze it.
Roast whole squash in a 400 degree oven for 1-2 hours, until a knife inserted into the fleshy top part pushes in without resistance. Remove, cool, and scoop out the flesh, discarding the seeds and fiborous bits from the middle of the bulb end. If you have a vacuum sealer you may want to use it to package your roasted squash, but this isn't necessary unless you plan to store it in the freezer for a long time. I usually just scoop mine out into ordinary resealable freezer bags. I like to freeze foods in amounts that I will use them. In this case I usually put about 4 cups of butternut in each freezer bag because that is the amount I use when I make this smooth, rich, delicious Roasted Butternut Squash Soup...
ROASTED BUTTERNUT SQUASH SOUP
4 cups roasted butternut squash
1 quart canned carrots, drained*
1 quart seasonal stock
1 (12 oz.) can evaporated milk
4 tablespoons butter (Leave this out or reduce the amount if you must, but using it really brings out the rich, sweet taste of the squash.)
1/2 teaspoon garlic powder
1/4 teaspoon white pepper
1/4 teaspoon black pepper
1 teaspoon salt (Seasonal Stock contains no added salt. If you are substituting purchased vegetable broth or chicken stock that contains salt you might want to add less salt)
*Although I have previously advocated against canning carrots, I do can some for use in some recipes. Using your frozen squash and canned carrots makes throwing this soup together a snap! Seriously, you can make this soup in less than 15 minutes. But you could roast fresh butternut and fresh carrots if you wanted to do everything the long way around.
Speaking of carrots, I have a handful of last summer's carrots remaining in storage and they are still nice and crisp, even though it is now April! You can read about my fabulous carrot storage system here.
Use a blender to puree roasted butternut, drained carrots, stock, and evaporated milk together in batches. Pour each batch into a large saucepot. Stir well to incorporate all batches of puree. Add butter and seasonings. Heat to a gentle simmer. Sprinkle some crumbled bacon, fresh grated parmesan cheese, or cracked pepper into each bowl. Serve with crusty bread or garlic toast.