Harvesting & Storing Squash

CR Lawn, 2009

When do you harvest squash? How do you cure it? How do you store it? Winter squash is a hearty satisfying treat on a cold winter day. Here are some tips for how to harvest, cure and store these fruits so they don't end up resembling the paste tense of their generic name.

The word “squash,” while conjuring distinct images, is not very descriptive. We are dealing with three separate species here (four if you are adventurous and grow Cushaw, a Cucurbita argyrosperma), as well as the so-called pumpkins. “Pumpkin” has no botanical basis, the small ones being C. pepo and the giant ones C. maxima.

C. pepo includes acorn and delicata squashes, zucchinis and summer squashes as well as pie pumpkins. They have 5-sided ribbed stems and the fruits are usually ribbed. While their stems give no indication of ripeness, the fruits characteristically turn color when they ripen. Acorns will darken and pie pumpkins turn to bright orange. Delicatas lose some of their green coloration and develop a yellow or orange undertone.

C. moschata are smooth and tan and include butternut squashes and cheese pumpkins. Butternuts typically have difficulty fully ripening in our climate. They are fully tan when ripe. If they retain even a hint of green, they aren't mature and their flavor will suffer.

C. maxima includes large squashes such as the buttercups, Japanese Kabochas and hubbards as well as the large Jack O'Lantern pumpkins. These have fat round stems that turn corky and woody as the squashes ripen. Maximas are the lone species that give away their ripeness by the condition of their stem. When the stem is fully wizened, they are dead ripe.

Good storage starts with good harvesting. Leave all squash on the vine until threatened by a hard frost. Even if they look ripe, leave any that you don't want to eat now. They engage in an after-ripening process that makes them sweeter and waiting is a good policy. Only if temperatures are heading for the 20s should they be severed. Then bring them in or cover them under a heavy tarp. I put spoiled hay over my tarp for added protection. As soon as the threat is gone and the sun comes out, remove the tarp. Nearly ripe squash are worth protecting, but don't bother to harvest squash that are way under-ripe. The only hope for these dilatory fruits is to leave them and hope they escape frost and buy some more time to mature in the field. If harvested immature they will not keep.

It is critical to keep the stems on the fruits. I therefore recommend using pruning snips, rather than tugging or twisting them off the vine. Any fruits that lose their stems must be eaten very soon for they will not keep long.

All squash should be sun-cured. Leave them in the field for 10-14 sunny days, covering if rain or frost threatens, then uncovering promptly when the threat abates. They will continue to after-ripen, developing their full sugars and delectable flavor. When nights become consistently cold, bring them indoors for keeps.

Once they are finally brought in, keep them above 50° F. Any place 50-70° with 60-70% relative humidity is ideal. But the root cellar is a no-no; it is too cold and damp and they will rapidly deteriorate.

Squash in storage are antisocial. Place them where they are not touching one another and where the air circulation is good. If you must heap them in a pile, mold can spread rapidly, so check frequently for mold spots and cull all those with such spots, and any others with soft spots or bruises.

Squashes vary widely in their storability. Some, such as the French Galeuse D'Eysines and the Winter Luxury pumpkin (notwithstanding its name) will be lucky to make it intact until Thanksgiving. Others, such as Australian heirlooms Queensland Blue and Triamble, cheese pumpkins and Long Pie, and some of the Japanese Kabochas will keep seemingly forever. The latter, often indifferent eating in fall, don't develop full flavors until late winter, when they are said by their devotees to be superb.

In general the acorn squashes are the first to get tough and stringy, followed by delicatas, buttercups and then later by pie pumpkins, butternuts and cheeses. Enjoy!