When cooked, the flesh separates into long, crunchy strands that resemble spaghetti, hence its name. It’s frequently used in dishes that call for pasta, and is a healthy alternative for it. Ripe spaghetti squash should be about 9 inches in length and feel heavy (6-9 lbs.). While it’s not necessary to refrigerate whole, uncooked spaghetti squashes, they typically last two to three months if kept in a cool, dark place. A few key indicators will help you tell if your spaghetti squash has gone bad.