Carved pumpkins look their best one to two days after carving, and rarely look good after seven days. It’s best to wait until October 24th, but if you just can’t, here are some tips for keeping your pumpkin designs fresh for a longer period of time.
Pumpkins begin decomposing from harmless bacteria and fungi in the air and on your hands. To avoid transferring bacteria to the pumpkin, first, wash your hands well with soap and water, or use a hand sanitizer. Second, thoroughly clean your carving tools with soap and water. Finally, wipe down the outside of the pumpkin with a 10% bleach solution before making your first cut.
Once carved, you can keep your pumpkin fresh for up to a week by either wiping both the inside and the cut areas with bleach, or by spraying your carving every day with a household cleaning solution that includes bleach. Be sure to keep the liquid from pooling in the bottom or under your pumpkin, as this can cause speed-rot. Lastly, give the cut areas of your pumpkin a thin coating of petroleum jelly to further preserve the carvings.
Carved pumpkins decay the fastest in warm weather. It’s best to keep them out of direct sunlight and move them into a garage, cool basement, or a refrigerator when temperatures exceed 70°F. If your climate is humid, or if it is rainy, you should dry off and refrigerate your carved pumpkins at night. Freezing temperatures also speed decay, so move carved pumpkins to a protected location when temperatures outside are below 32ºF.
If a pumpkin starts to prematurely shrivel or get moldy, revive it by soaking it in a bucket of water with a disinfecting solution of two teaspoons of bleach for every gallon of water.
To light up your pumpkin carving for more than one night, use a battery-operated candle or small flashlight instead of a candle. This will prevent soot and heat damage that could shorten the pumpkin's lifespan.