Like many parts of the Upper Midwest, we seem to be having an early harvest season this year. Pumpkins and fall squash should be harvested when skin is tough and doesn’t yield to gentle fingernail pressure. Stems should be dry.
Research shows jack-o-lantern size pumpkins reach full color 45 days after fruit set and stems harden in 20-35 days after fruit set. This is for ideal growing conditions and may take longer if there is shade, drought, disease or other stresses.
Know that conditions both before and after harvest affect storage life. Vines that are healthy up to harvest make for a longer keeping pumpkin. Likewise, favorable storage conditions after harvest make a difference too.
Cut the stem with hand pruners to preserve stem health. Solid stems provide an effective barrier to rot. Use care in moving pumpkins to avoid nicks, scrapes and other mechanical injury. Move when the surface of the fruit is dry to be able to get a firm grip on fruit among other reasons. They keep better if harvested before frost and sustained periods under 40 degrees F.
Store in a shaded, dry area with good ventilation. The best storage temperature is 50 to 60 degrees F. This temperature is likely difficult for most people to achieve, particularly with hot weather lingering late into September this season.
Healthy fruit that is harvested and stored under favorable conditions can last up to 6 months. If you want fruit to last until Halloween, that is a reasonable goal. Storage until Thanksgiving will take a little more attention to each step of the growing and harvesting process.
Photo credit: Standard and flat French pumpkin types – both Carl Wilson