image by Eduardo Guillen: sxc.hu
Pumpkins (Cucurbita pepo) are fall crops that are a type of squash. In addition to being used for decorations, they are wonderful in soups, stews, bread and desserts. Like squash, pumpkins grow on a vine. Giant pumpkins (C. maxima) can be grown to show at fairs.
Determine which type of pumpkin seeds to purchase. Small pumpkins (pie pumpkins) have smaller, sweeter fruit. Pumpkins mainly used for jack-o'-lanterns are generally not eaten since the flesh is so bland and stringy. The seeds can be roasted, however. The other option is giant pumpkins, which are grown for show.
Choose a planting site that has full sun or light shade and well-drained soil. The optimal soil pH range for vine crops is 6 to 6.5 (slightly acidic). Make sure the soil is at least 65 degrees F before you plant the seeds--late May to early June is generally the best time. Till the soil 12 to 15 inches deep and add a 2-to-4 inch layer of compost.
Sow the seeds of vining pumpkins 1 inch deep in a circle that is about 2 feet in diameter. Space the circles 2 to 3 feet apart in rows that are 6 to 8 feet apart. Plant miniature pumpkins 1 inch deep with two or three seeds every 2 feet per row. Rows should be 6 to 8 feet apart. Plant semi-bush varieties 1 inch deep with four or five seeds per hill. Allow 4 feet between hills and 8 feet between rows. Plant bush varieties 1 inch deep with one or two seeds per foot of row. Allow 4 to 6 feet between rows. Cover the seeds with soil. Pumpkins require a long growing season--approximately 75 to 100 frost-free days.
Water the pumpkins with at least 1 inch of water (from rainfall or irrigation) per week during growing season. Soak the soil thoroughly when watering. Water sandy soil more frequently, but with less water per application.
Cultivate shallowly with a garden hoe or hand trowel to kill weeds. The roots of vine crops stay close to the surface, so take care not to go too deep. When cultivation is no longer possible, pull weeds by hand. Consider using mulch to keep the weeds down. Pinch off the fuzzy ends of each vine after a few pumpkins form.
Harvest the pumpkins when you are able to thump the pumpkin lightly with your fingers and hear a hollow response. That means the pumpkin is ripe. You can also press a fingernail into the skin. A ripe pumpkin will resist puncture. Use a sharp knife or pruners to cut pumpkins from the vine, leaving the long stem as a handle.