When you take your family trick-or-treating this Halloween, take a closer look at your neighbors' decor. Among the fake spiderwebs and skeletons, you may notice pumpkins that have been painted teal, purple, or blue. Unlike your typical jack-O'-lantern, these gourds aren't there just for decoration. Painted pumpkins may have a special meaning that corresponds to their shade.

Teal may be the most common pumpkin color you see on October 31. Since launching in 2014, the Teal Pumpkin Project has encouraged households to put teal pumpkins outside their houses to indicate they're allergen-friendly. Instead of giving out candies that may contain ingredients like nuts, eggs, or soy, teal-pumpkin homes offer non-edible treats like small toys.

The success of the Teal Pumpkin Project has boosted similar initiatives tied to Halloween. The Epilepsy Foundation is behind the Purple Pumpkin Project, which aims to raise awareness around the condition. A purple pumpkin on someone's doorstep is meant to be a conversation starter that gets neighbors talking about epilepsy and the challenges of living with seizures. Someone might display a purple pumpkin outside their home to signal that a person with epilepsy lives there—or to show that they will know how to respond if a trick-or-treater has a seizure.

Darker blue pumpkins are associated with autism. Alicia Plumer first had the idea to use a blue jack-O'-lantern bucket to indicate that her son has autism on Halloween in 2018. After her social media post went viral, families of autistic kids across the country started using blue buckets. The color indicates that certain social interactions—like making eye contact or saying "thank you"—may not come naturally to those trick-or-treaters. The color is most often seen in candy buckets, but some households will paint real pumpkins dark blue and display them outside. If you see a blue pumpkin on someone's porch, it likely means that the household welcomes any visitors with the condition.

Trick-or-treating may feel more complicated today than when you were a kid. Luckily, it's easier than ever to optimize the night and maximize your kids' candy haul. Here's a tool for planning the perfect trick-or-treating route this Halloween.