Waiting until just before Halloween or Thanksgiving to buy a pumpkin can seem old-fashioned.
Given how early pumpkins go on display and how long they stay there, today’s varieties appear to have real staying power. The supply implies the orange orbs might as well become decorations instead of waiting for weeks on a store shelf.
“Plant breeders are, in fact, always working to develop pumpkins with a longer shelf life,” said Ward Upham, horticulturist with K-State Research and Extension. “You have to remember, though, that store displays aren’t static. Replacement stock keeps coming in until the season is almost over. Pumpkins that go bad disappear.”
To help eager buyers identify pumpkins with the best odds for lasting, Upham developed the following list of characteristics. The best pumpkins will be:
– Whole, which can include pumpkins with a painted face. Carved jack-o’-lanterns last about a week.
– Stemmed. This is most important for outdoor pumpkins. Lost stems leave a depression behind that will collect water, snow or ice, promoting spoilage.
“That’s why no one should ever carry a pumpkin by its stem, even while they’re shopping,” Upham said.
– Dry-stemmed. Almost all commercial varieties now have green stems, so “mature” stem color no longer matters. A stem that is leaking sap, however, indicates the pumpkin was too young for harvesting.
– Fully mature. Size, rind color and shape are not usable criteria anymore, but buyers can try to pierce the rind with a thumbnail, which is easy with immature pumpkins and difficult with those that are ripe.
“The rind has to be hard enough to keep moisture from escaping,” Upham said. “Otherwise, the pumpkin will shrivel.”
– Blemish-free, with no soft spots. This characteristic does not include the bumps and hard “pimples” that are natural for some varieties. Instead, blemishes are the result of injuries that have damaged pumpkin tissue and perhaps provided access for bacteria or led to “scarring.”
“We started getting more smooth varieties when pumpkin painting first became popular,” Upham said. “A lot of people still like the bumps and ‘warts,’ though. Some think they’re more naturalistic-looking. Others use them to make decorations ‘scarier.'”
– Cured. This can be difficult to assess if store owners did not check into that and are unable to answer questions. Holiday fans who select their pumpkin in a field, however, should cure it for about 10 days, preferably in temperatures of 80 to 85 degrees Fahrenheit and a relative humidity of 80 to 85 percent.
“Just doing the best you can at creating those conditions will help,” Upham said.
– Dry and cool. Cured pumpkins don’t do well in wet conditions, and although pumpkins thrive in cool weather, harvested pumpkins respond badly to cold. They start to degrade when temperatures fall below 50 degrees F. They turn into mush overnight when they freeze.
“That’s something to keep in mind when you look over a pumpkin display. Store owners may be having indoor space problems, but they still need to find ways to store their pumpkins well,” Upham said. “After all, a century ago, you would have had your own pumpkin harvest, and you would have put it in the attic, because your basement or root cellar was too damp.
“Keeping pumpkins dry and cool is also something to keep in mind when you’re using pumpkins outdoors. To keep them in good shape, you’ll need to keep them out of expected rainfalls and bring them in whenever the nights are cold.”