Pumpkins are a warm-season annual that require from 90 to 120 frost-free days to reach harvest. Grow pumpkins in the warmest, frost-free part of the year.
- Sow pumpkins in the garden in spring when all danger of frost has passed and the soil temperature has reached 65°F (18°C) and night air temperatures are above 55°F (13°C). In cool-summer regions grow smaller varieties.
- Start pumpkins indoors 2 to 3 weeks before the average last frost date in spring; transplant them into the garden 2 to 3 weeks after the last frost.
- Plant pumpkins in full sun; pumpkins will tolerate partial shade but full sun is preferable.
- Pumpkins grow best in loose, well-worked, well-drained soil rich in organic matter. Add aged compost to planting beds in advance of sowing.
- Pumpkins prefer a soil pH of 6.0 to 6.8.
- Plant pumpkins on a hill mounded 6 inches or more above the garden. The mound will collect solar heat which will enhance growth. A mound 36 or more inches across will support three plants.
- Work plenty of aged compost and aged manure or commercial organic planting mix into the hill before planting.
- Pumpkins require ample room for growth. Vining varieties sprawl and may require between 50 and 100 square feet of space. Bush varieties require less space than vining varieties.
- Pumpkin vines planted on a mound can be trained in an ever-widening circle around the mound.
- Pumpkins also can be planted in beds covered with black plastic sheeting. The black plastic will warm the soil. Cut a hole in the plastic to plant seed or transplants.
Starting Pumpkins Indoors
- Pumpkins can be started indoors 2 to 3 weeks before the average last frost date in spring for transplanting into the garden 2 to 3 weeks after the last frost.
- Start seeds in individual peat pots or biodegradable containers. The roots of pumpkin seedlings are very sensitive. Start seed indoors in peat pots then set individual pots and seedlings into the garden together at transplanting time.
- Sow seed 1 inch (2.5cm) deep.
- The seed will germinate in 5 to 10 days at 70°F (21°C).
- Pumpkin seed coats are hard. To speed germination soak seeds in warm water or 1 hour before planting. The long edges of seeds also can be lightly filed with a nail file; this will weaken the seed coat and speed germination.
- Grow seedlings indoors under grow lights of fluorescent lights. Keep the soil evenly moist.
- When transplanting seedlings to the garden make sure the rim of the peat pot is not exposed to the air or it will wick moisture away from the plant’s roots.
Starting Pumpkins in the Garden
- Direct sow pumpkin seeds in the garden 2 to 3 weeks after the average last frost date when the soil temperature has reached 65°F (18°C) and night air temperatures stay above 55°F (13°C).
- The optimal soil temperature for starting pumpkins in the garden is 70°F (21°C) or warmer.
- Keep floating row covers handy to protect young plants from chilly night temperatures or unseasonal weather. Pumpkins are very sensitive to cold soil and frost.
- In cool-summer regions grow smaller, quick-maturing varieties.
- In warm-winter regions or very hot summer regions, plant pumpkins in late winter for harvest in late spring.
Planting and Spacing Pumpkins
- Plant pumpkins on raised mounds 6 to 12 inches (15-30cm) high at least 24 to 36 inches (61-91cm) across. Larger is better. At the top of the mound, you can remove an inch of soil to build up a rim around the edge of the mound creating a basin for watering.
- Space hills 6 to 8 feet (1.8-2.4m) apart.
- Sow pumpkin seeds 1 inch (2.5cm) deep.
- Sow 6 to 8 seeds in each hill.
- When seedlings are 2 to 3 inches (5-7cm) tall, thin to the 2 or 3 strongest seedlings. Cut off thinned seedlings at soil level to avoid disturbing the roots of the remaining plants.
- Thinned seedlings should be spaced 18 to 36 inches (45-91cm) apart.
- Pumpkins growing in rows should be spaced 24 inches (61cm) apart and rows should be 6 to 10 feet (1.8-3m) apart.
- Grow 1 to 2 pumpkin plants per household member.
More tips at Pumpkin Seed Starting Tips.
Container Growing Pumpkins
Pumpkins require a great amount of space and so they are not good candidates for container growing. However, you can grow a small, space-saving variety in a 10-gallon container. Train the vines to grow around the container. Keep the soil in containers evenly moist throughout the growing season. Feed plants compost tea or diluted fish emulsion every two weeks.
- Plant pumpkins with corn. Avoid planting pumpkins with potatoes or squash.
- Plant flowering herbs such as dill or bee balm near pumpkins to attract bees and other pollinators.
- The first flowers to appear on the pumpkin plant will be male flowers which do not bear fruit. Male flowers appear about a week before female flowers. They attract bees and other pollinators.
- Female flowers appear on the plant after male flowers. Female flowers will bear an immature pumpkin beneath the blossom at the stem end of the flower. Female flowers must be pollinated by bees that first visit male flowers.
- Plant flowering herbs such as dill, bee balm, and marigolds close to pumpkins to attract bees and other pollinators.
- If pollinators are in short supply, pumpkins can be hand pollinated. Use a small artist’s bristle brush to collect pollen from a male flower then brush the pollen onto the pistil at the center of the female flower.
- Pumpkin blossoms are usually open in the morning then close in the afternoon during the warmest of the day.
Watering and Feeding Pumpkins
- Pumpkins require regular, even water to keep vines and fruiting growing without interruption. Give pumpkins 1 to 1½ inches of water each week (1 inch/2.5cm of water equals about 16 gallons/60.5 liters).
- Do not let the soil dry out. Slow, deep watering is best.
- Water at the base of plants using drip irrigation of a soaker hose. Avoid wetting leaves; wet leaves are susceptible to fungal diseases.
- Add aged compost and manure or commercial organic planting mix to the planting area before planting.
- Feed pumpkins an organic fertilizer high in phosphorus once plants are established; a 5-10-10 formula is good.
- Side dress pumpkins with compost or manure tea or a dilute fish emulsion solution every two weeks during the growing season.
Caring for Pumpkins
- Keep the planting area weed-free. Weeds compete for soil moisture and nutrients and harbor pests and diseases which can attack pumpkins.
- Allow just 2 or 3 fruits to mature on each plant.
- Set developing fruits on tiles, sheets of plastic, or wooden shingles so that they do not develop rot sitting on wet soil.
- Turn pumpkins as they develop to encourage an even shape. A pumpkin that is not turned may have a flattened side at harvest time.
- To grow pumpkins for large size, choose two or three fruits early for development; remove the remaining fruit and vines.
- When pumpkins have formed on a plant, pinch or snip off the fuzzy end of each vine. This will stop vine growth and the plant will put its energy into fruit growth. Vines without fruit can be pruned back to about 2 feet long.
- Remove new female flowers from vines once two or three fruits are growing on a plant.
- Pumpkins can be attacked by squash borers and cucumber beetles.
- Squash vine borers will drill a small hole in the stem. Unexplained wilting may indicate the presence of borers. To remove a borer, slit the stem lengthwise, remove the borer, and crush it. Cover the slit stem with soil to encourage root development from that point.
- Spotted and striped cucumber beetles chew holes in leaves and can spread bacterial wilt and other diseases. Handpick and destroy cucumber beetles or spray with neem or pyrethrum.
- Squash borers or bacterial wilt can cause squash plants to suddenly wilt and die just as they begin to produce.
- Pumpkins are susceptible to bacterial wilt, mosaic virus, and mildew. Plant disease-resistant varieties.
- Keep the garden clean and free of debris where diseases and pests may harbor. Water at the base of plants to keep water off the foliage, and do not handle plants when they are wet to avoid the spread of fungal spores.
- Remove and destroy infected plants before they spread the disease to healthy plants.
- Bacterial wilt is spread by cucumber beetles. Bacterial wilt will cause pumpkin plants to suddenly wilt and die just as they start to produce pumpkins. Control the beetles to control the spread of disease.
- Mosaic virus can cause squash plants to become mottled yellow and stunted. Mosaic virus is spread by aphids. Control aphids and remove affected plants.
- Powdery mildew, a fungus disease, will cause leaves to turn a gray-white color late in the season. Proper spacing and increased air circulation will help reduce this problem.
Harvesting and Storing Pumpkins
- Pumpkins will be ready for harvest 95 to 120 days after sowing depending on the variety.
- Pick pumpkins when they are deeply colored–deep orange or golden white–and stems and vines have dried and turned brown.
- The rind should be hard, not easily penetrated by a fingernail.
- Thump maturing pumpkins; a ripe pumpkin will sound hollow when thumped.
- As pumpkins mature, remove leaves that shade the fruit to allow for maximum sun exposure.
- As pumpkins near harvest, vines may begin to yellow and shrivel away.
- Use pruning shears to cut the vine; leave 2 to 4 inches (5-10cm) of stem attached to the pumpkin so that the fruit does not readily dry out or decay.
- Harvest pumpkins before the first freeze or they will turn soft.
- Seed saved from heirloom or open-pollinated pumpkins can be saved for up to 6 years for replanting.
Storing and Preserving Pumpkins
- Cure pumpkins in direct sun at 75° to 80°F (24-26°C) for 2 weeks before storing.
- Store pumpkins at 50° to 55°F (10-13°C), in a dry, well-ventilated place.
- Do not refrigerate pumpkins.
- Cured pumpkins can be stored for 3 to 6 months.
- Pumpkins in storage can shrink as much as 20 percent in weight but will still be suitable for cooking.
- Pumpkin can be pureed and frozen for up to 6 months. Pumpkin also can be frozen or canned.
More tips: How to Harvest and Store Pumpkins.
Pumpkin Varieties to Grow
Grow small pumpkins for cooking; grow intermediate and large sizes for cooking and for making jack-o’-lanterns; grow extra-large pumpkins for an exhibition.
- Extra-large (50 to 100 pounds): ‘Atlantic Giant’ (125 days); ‘Big Max’ (120 days); ‘Big Moon’ (120 days); ‘Mammoth King’ (120 days); ‘Prizewinner’ (120 days); ‘The Great Pumpkin’ (120 days).
- Large (15 to 25 pounds, 100 days): ‘Aspen’ (93 days); ‘Connecticut Field’ (120 days); ‘Ghost Rider’ (115 days); ‘Half Moon’ (115 days); ‘Howden’ (115 days); ‘Pankow’s Field’ (120 days); ‘Pro Gold’ (95 days); ‘Tallman’ (110 days); ‘Wizard’ (115 days).
- Intermediate (8 to 15 pounds): ‘Autumn Gold’ (90 days); ‘Big Autumn’ (100 days); ‘Jack O’Lantern’ (115 days); ‘Oz’ (105 days); ‘Small Sugar Pie’ (110 days); ‘Tom Fox’ (110 days); ‘Trick or Treat’ (105 days).
- Small (4 to 6 pounds): ‘Bush Spirit’ (100 days); ‘Frosty’ (95 days), ‘Wee-B-Little’ (90 days).
- Others: ‘Baby Bear’ (105 days); ‘Baby Boo’ (95 days); ‘Buckskin’ (110 days); ‘Casper’ (80 days); ‘Cushaw, Green Striped’ (110 days); ‘Gremlin’ (100 days); ‘Japanese Pumpkin’ (110 days); ‘Jarrahdale’ (110 days); ‘Lady Godiva’ (110 days); ‘Little Gem’ (110 days); ‘Little Lantern’ (100 days); ‘Long Cheese’ (120 days); ‘Lumina’ (110 days); ‘Munchkin’ (110 days); ‘Rouge D’Etampes’ (95-160 days); ‘Sweetie Pie’ (110 days).
Favorite Pumpkins to Grow
- ‘Jack Be Little’ is a miniature pumpkin for table decoration.
- ‘Wee-B-Little’ is an All-America Selection, the size of a baseball.
- ‘Autumn Gold’ is ideal for carving a Jack-o-Lantern.
- ‘Sugar Treat’ and ‘Baby Bear’ are excellent for pies.
- ‘Atlantic Giant’ and ‘Big Max’ grow to 200 pounds by county fair time.
More varieties to grow: Pumpkin Varieties: Best Bets and Easy to Grow.
- Pumpkins are tender squash-like annuals with smooth rinds scored with vertical grooves.
- Fruits can range in size from a few ounces to hundreds of pounds and in color from deep orange to white. Some heirloom varieties can be swirled multi-colored.
- Large, green leaves grow on branching vines that can reach 20 feet long.
- Large male and female flowers grow on the same vine.
- The name pumpkin is also given to other hard, orange squashes and gourds.
- Botanical name: Cucurbita maxima, Cucurbita moschata, Cucurbita pepo
- Origin: Tropical America
More tips: Pumpkin Size: Cooking and Carving.