Growing Tips: Pumpkin


Quick Reference:

In Alaska, garden soils are too cold at planting time for pumpkin seed to germinate so the seed MUST be germinated indoors in plastic pots. Pumpkin seed germinates in 10 to 14 days when the soil temperature is above 60 degrees F. Plant  two or three seeds 1/4 inch deep in a 4 inch plastic pot filled with rich loam 4 to 6 weeks before the last frost.

When and where to plant:

Pumpkins require warm sunny weather, warm soils and a long season to mature. For pumpkin seed to germinate the soil temperature must be in the mid to upper 50's at planting time and fruits will mature in the garden only in the warmer areas of Alaska. When growing pumpkins it is recommended that a soil warming technique like raised beds or mounding be used. Pumpkins do best when the seed is planted where the plants will grow all season. Pumpkin roots are tender so the seedlings must be transplanted with care. Where soils are cold at planting time, start seed indoors 4 to 6 weeks before the last frost. Plant 2 or 3 seeds in individual 4 inch plastic pots filled with a good rich loam 4 to 6 weeks before the last frost. The plastic pots allow the roots to slide out easily minimizing root damage during transplanting. When the seedlings are 2 inches tall clip off all but the two healthiest seedlings, water with a half strength solution of liquid plant food weekly and grow in full sun until the garden is ready. After the last frost, plant seed or seedlings outdoors in a rich, well drained soil, using raised beds or a mound to help warm the soil. When using the mound method, form a mound 8 to 10 inches high by 14 to 16 inches wide at the top, apply plant food, then plant the seedling in the center of the mound. Covering the mound with a clear plastic mulch weighted with soil on all four edges for a greenhouse affect then planting through the mulch will even further raise the soil temperature. Ignore the weeds that will grow under the mulch. When transplanting, water the soil in the pot when carefully slide the root ball out of the plastic pot and place seedling a in hole filled with water, push moist soil around the root ball. When planting seed, firm soil over seed, water well and keep soil moist until seedlings emerge.                           


Keep the soil moist and apply plant food once a month. Where the air is cool use a clear plastic windbreak to keep wind off the plants. Do not worry if the first blossoms do not set fruit. After the plant has set 2 or 3 fruits remove the rest of the female blossoms to help mature existing fruits.


Cut the fruits leaving some stem on the fruit before the first frost. Cure fruits in a warm dry spot. Immature fruits will gain some color after they are harvested but will not keep well.