Squash, Gourd, and Pumpkin

Squashes prefer a well drained, sandy loam with high organic matter content and a pH of 6 to 6.5. See Soil Management for suggestions on liming materials and increasing soil organic matter.

Summer squash. Summer squash is fast growing and requires relatively high fertility, especially before flowering. Harvesting one ton of fruit removes 2 pounds N, .8 pounds P2O5, and 3 pounds K2O from the soil. Inadequate availability of calcium to the fruit sometimes results in blossom end rot and internal browning. Although little studied in squash, presumably the disorder is similar in cause and prevention to blossom end rot in tomatoes. Plant nutrient additions based on soil test results are presented below.

Winter squash. Harvesting one ton of winter squash removes 2 to 3 pounds N, 0.8 to 3 pounds P2O5, and 1.8 to 5 pounds K2O from the soil. Recommendations when soil test results are not available are to apply 50 pounds N, 100 pounds P2O5 and 100 pounds K2O preplant with two additional applications of 25 pounds N and 80 pounds K per acre at 3 and 6 weeks. Plant nutrient additions based on soil test results are presented in Table 16.3. See Chapter 1 for organic sources of these nutrients.

Planting

Pumpkins and squash are generally direct-seeded about 1-inch deep into 5-to-8-inch high raised beds prepared 7 to 10 days in advance. Cucurbits generally do not transplant well and the benefit in terms of earliness is less than with shorter-season crops.

Between row spacing should be 5 to 8 feet for pumpkins and 3 to 4 feet for bush squash. Within row spacing should be 3 to 4 feet for pumpkins and 2 to 3 feet for bush squash. Zucchini requies more space than yellow squash or scallop cultivars.

Squash nutrient recommendations based on soil tests

In Indiana, zucchini grown with plastic mulch and drip irrigation had 35 to 45 percent higher yields compared to plants grown on bare ground. Fruit quality was also increased by drip irrigation.

Squash cultivars with insect and disease resistance