Expected first and last frost dates are based on averages from the past. Sometimes we get freezing temperatures “early” and sometimes “late.” This year it seems winter is anxious to arrive, and we’ve been hit with colder temperatures earlier than expected. Most of the time we don’t see fall temperatures of 25°-28° F until mid to later October. Elevated heating costs and an abrupt halt to fresh tomatoes aren’t the only consequences to early freezing temperatures.
While it’s a minor consideration, an early cold snap can lead to a quick deterioration of your Halloween pumpkins. Following a few simple tricks can help you maintain your jack-o-lantern’s smile.
First and foremost, protect your pumpkins from freezing. A light frost will not damage the pumpkins themselves, but mature pumpkins should be harvested before temperatures drop below 25° F. A freeze damages the skin and allows rot-causing fungi and bacteria to enter the inner tissues. When harvesting pumpkins, avoid cuts and bruises and leave several inches of stem attached for the same reason. A pumpkin with a three to five-inch stem is more attractive and less likely to rot.
After harvest, pumpkins need to be cured at a temperature of 80° to 85° F, with a relative humidity of 80 percent for 10 days. Curing helps harden their skins and heal any cuts and scratches. Curing also enhances color and ensures a longer post-harvest life. Skipping this step doesn’t doom your pumpkin, but it is effective.
To ensure the pumpkin lasts a long time, it can be cleaned or sprayed with a 10 percent bleach solution. Afterwards, store pumpkins in a cool, dry place. Storage temperatures should be 50° to 55° F. When storing pumpkins, place them in a single layer where they don’t touch one another. Good air circulation helps prevent moisture from forming on the surfaces of the fruit and retards the growth of fungi and bacteria. Promptly remove and discard any pumpkins that show signs of decay. Pumpkins that are harvested, cured, and stored properly should be in excellent condition for painting or carving, or for use in fall decorations, and can be stored for several months.
After carving your pumpkin, you can lengthen its toothy smile by continuing to protect it from freezing, from rot, and from dehydration. Spraying your pumpkins, including the inside, the edges and all cut openings with a mixture of one tablespoon of bleach per quart of water can get rid of all the mold and mildew. There are also several commercial pumpkin preservative sprays such as Pumpkin Fresh and Pumpkin Dunk’N. These contain water, borax and sodium benzoate as a fungicidal solution that kills bacteria and mold.
Acrylic spray, vegetable oil and even WD-40 are all options to help prevent your carved pumpkin from dehydrating. A thin layer sprayed or wiped over all surfaces can impede moisture from leaving your pumpkin. Overtime, pumpkins tend to start drying out and shrivel as they lose water content. In order to revive a dried-out pumpkin, submerge it in water overnight or at least, for a few hours. Make sure to dry your pumpkin and re-apply preserving treatments following rehydration.