A pumpkin seed, also known in North America as a pepita, is the edible seed of a pumpkin or certain other cultivars of squash. The seeds are typically flat and asymmetrically oval, have a white outer husk, and are light green in color after the husk is removed.
Pumpkins are actually a type of winter squash. Many varieties can send out vines that are 10 to 20 feet long, which can be challenging for a raised-bed garden. One option is to grow them on a trellis, such as the Cucumber Trellis. Use a mesh bag or fabric to help support especially heavy fruit. Another technique is to plant them on an outside corner of your raised bed and let the vines ramble onto the grass.
Like summer squash, winter squash need rich soil that's been amended with compost. They need warm weather and warm soil to grow and produce well. In most cases, it takes 90 to 100 days from planting seeds until the squash are ripe. Cold-climate gardeners may want to get an early start by planting seeds indoors about three weeks before the last spring frost. Plant two seeds per 3" pot, and cut off one if both grow.
Transplant into the garden a week or two after the last spring frost. You can warm the soil by covering it with clear plastic, which works better than the traditional black plastic, as long as you seal the edges with soil to contain the heat.
Some winter squash and pumpkins — the bigger ones, generally — will only produce a couple of fruit per plant. The seed catalog or seed packet should tell you what to expect. Pumpkins are always fun for kids, but not always good for pie. If you want jack-o-lanterns, you can grow any variety; for pies and soups, look for "pie pumpkins" or "sugar pumpkins," which have sweeter, more flavorful flesh.