Harvest Time for Winter Squash and Pumpkins

Storage conditions for crops like winter squash and pumpkins are different from most other vegetables. They prefer a cool, but not cold, storage temperature (between 50 and 55 degrees F.) and a fairly low humidity. They should not be placed in outdoor pits or cellars where humidity is too high and temperatures are normally too cool. Only well matured fruits of these plants store well. The rind should be hard, and there should be no damage from handling or from insect pests. Any wounds can make the fruit more susceptible to rot.

Harvest winter squash and pumpkins before frost. A light frost is not generally damaging, but for longest storage it is best not to expose them to freezing temperatures. Cut the fruit from the vine with a portion of the stem remaining. The open would which results if the stem breaks off directly at the base of the fruit can reduce storage life. Pumpkins and winter squash need a curing period to improve their keeping quality. After they are cut from the vine, they should be placed at temperatures close to 80 degrees for about 10 days. In the fall, this may be in a basement close to the furnace, in a warm closet, or in the attic if temperatures do not run too high.

During this time any wound which may have occurred during hardening or from insects has a chance to heal over, and the callus tissue formed helps prolong storage life. The rind will also become harder during this period. Bruises caused from dropping or throwing do not heal, however, and storage life can be reduced. Always handle winter squash and pumpkins as carefully as possible during harvest and moving.

After the 10-day curing period, the winter squash and pumpkins should be moved to a permanent storage location. Well ventilated shelves in a dry area are best. At no time should the surface of the fruit become wet. Store them in a single layer so that air can move all around each fruit. Most types will be subject to damage by chilling if stored below 50 degrees. At temperatures above 60 degrees they lose moisture too fast and gradually become stringy.

Even under the best storage conditions some weight loss will occur because of the loss of water and carbohydrates. During storage there is a gradual change within the fruit, so a change in quality can be expected. The Hubbard, butternut and buttercup types of winter squash are among the best keeping types. Acorn squash is an exception to the storage conditions given for the other types of winter squash. It should not be given the curing period, since it will often become stringy if exposed to the 80-degree temperatures for 10 days. It needs cooler storage than the other types and should be placed in 45 to 50 degree temperatures immediately after harvest. Under these conditions it should store well for 6 to 8 weeks.

http://www.ces.ncsu.edu/depts/hort/hil/hil-24.html