How to Grow Pumpkins From Seed

Pumpkins love heat and hate frost, whatever type you grow. Wait until the last spring frost has passed and the soil has warmed to 65 to 70F, usually late spring, before you direct-sow. Days to maturity run roughly 90 to 120 depending on the variety, with small pie and mini types finishing first and big carving and giant pumpkins taking the longest. Gardeners in short-season areas should start seeds indoors two to three weeks ahead, and lean toward the quicker-maturing types, then set out the young plants once the ground is warm.

Pumpkins grow best planted in hills of rich, well-drained soil in full sun. Sow four to five seeds about one inch deep in each hill, spacing seeds 6 to 8 inches apart. Set hills 4 to 6 feet apart for big carving and field types that run long vines, and 3 to 4 feet apart for compact bush or mini varieties. Seedlings break ground in 7 to 14 days once the soil holds at 65 to 70F. When the plants have a couple of true leaves, thin each hill to the best two or three, and give the whole patch open ground to sprawl into.

Once the vines take off, they grow fast and drink deeply. Give pumpkins a steady 1 to 2 inches of water a week, aiming at the base of the plant rather than the leaves to keep mildew down. A layer of mulch holds moisture and keeps weeds off the wandering vines. These are heavy feeders, so plant into rich soil and feed through the season. Be patient, since the larger types take most of the summer to size up and color, while small pie and mini pumpkins come in sooner.

Pumpkins share the garden well with plants that pull in pollinators and steer pests away from the sprawling vines. These heirloom, non-GMO companions earn their spot in the patch:

Pumpkins are ready when the rind turns deep, even color and grows hard enough to resist a press from your thumbnail, and the stem near the fruit goes corky and dry. Most types color up orange, though some varieties ripen white, tan, blue, or striped. Cut each pumpkin from the vine with a few inches of stem still attached, and lift it from underneath rather than by the stem. Let the fruit cure in a warm, dry place for about ten days to toughen the skin so it stores well into the fall and winter.

Pumpkins are as varied as their uses. Big carving and field types are the traditional pick for jack-o-lanterns and fall porch and table decor. Small, sweet pie or sugar pumpkins have fine-grained flesh that cooks down into a rich puree for pies, soups, and breads. Giant pumpkins are grown for the sheer spectacle of size, while mini and ornamental types make tidy decorations. Do not forget the seeds from any type, which roast into a salty, crunchy snack.

• Squash vine borer: a grub that tunnels into the stem and wilts the vine. Watch for holes near the base and cover young stems, or slit the stem to remove the borer.
• Squash bugs: gray bugs that cluster and suck sap. Crush the copper-colored egg clusters under leaves and knock the bugs into soapy water.
• Powdery mildew: a white coating on the leaves in warm, humid weather. Space plants for airflow, water at the soil, and remove badly hit leaves.
• Poor pollination: flowers but no fruit means too few bees moving pollen. Plant flowers nearby to draw pollinators, or hand-pollinate on a calm morning.
• Fruit rot: pumpkins that sit on wet ground can rot underneath. Slip a board or straw pad under each ripening fruit to keep it dry.