If it seems like your pumpkin doesn’t last longer than a week after it’s carved, then you’re probably right. As soon as you cut a shape on the front of the pumpkin or even create a display with those that you don’t cut on, the pumpkin begins to rot. There are a few tricks to help keep your orange centerpiece from rotting as quickly, possibly extending the life by a few months.
Soak the pumpkin in bleach to keep it from rotting for about seven days at a time.
The chemicals will kill organisms that seem to plague the outside of the pumpkin, causing it to rot. WD-40 can keep the pumpkin hydrated, which is an important component when it comes to making sure it stays alive and well for several days after the Halloween holiday.
Another tip is to put petroleum jelly along the edges that have been cut. This will help to prevent these areas from drying out as quickly, similar to what you would do for chapped lips.
Vegetable oil works in the same manner. You can also put a light glaze of oil on the outside of the entire pumpkin to lock in the moisture so that it doesn’t dry out.