Imagine you open up a CSA box—a kit of produce from community supported agriculture—only to find an apple covered in ashen warts. You’d probably be inclined to kill it with fire, or at least condemn it to the compost.

But if that fruit were a species of Cucurbitaceae—the gourd family—you might have an entirely different reaction, proudly displaying the knotty, mutated produce on a console table in your foyer. Blemishes are boons in many Cucurbit fruits, and when it comes to gourds, the funkier they come, the more we cherish them. One seed supplier even champions something called a “blister gourd” as being “larger and more warted” than lesser, more symmetrical varieties.

As the leaves turn to tints of reddish-orange, it’s time to trek to farmers’ markets and pumpkin patches to bring home the knobbiest, knurliest and gnarliest Cucurbit fruits you can find—that’s right, it’s decorative gourd season once again, folks. Though their flesh be adamant and their seeds bitter, thousands of decor enthusiasts will flock to the farm to pick out gourds for arrangements spilling out of wicker baskets or piled on dining table centerpieces.

But before the gourd became the unofficial, freaky flower of fall, the hard-nosed fruits enjoyed a rich history. It’s tempting to think of our ornamental gourd obsession as a fad, like pumpkin spice lattes or puffy down vests, but Americans have been geeking out over gourds since at least 1937, when the first chapter of the American Gourd Society was established in North Carolina. There are now gourd chapters in 24 U.S. states.

And that’s not even the half of it. Scientists have found evidence that humans have been cozying up to gourds for at least 8,000 years. In that time, we’ve selectively bred the bumpy little dickens for all sorts of purposes.

Today, decorative gourds come in dozens of varieties, from mace-like Shenot Crown of Thorns gourds and smooth-necked Speckled Swan gourds , to the deep-veined Dinosaur gourds and Yugoslavian finger gourds , which resemble tiny, sun-bleached skulls. Watermelons and cucumbers also belong to the Cucurbitaceae family, though we don’t call them gourds. In fact, gourds aren’t even a classification of anything, scientifically speaking.

“In English, we use the term ‘gourd’ to refer to the wild and weedy types,” says Laura Merrick , a botanist at Iowa State University who has spent nearly 20 years investigating the Cucurbita genus. “They’re small and hard-rinded and very bitter, so they’re not typically eaten.”

Of course, there are some gourd relatives that make for good eating. Edible varieties tend to go by “squash” or “pumpkin,” valued for the sweetness and tenderness of their flesh. Over time, selective breeding has given us treats such as butternut squash and zucchini, and other Cucurbit fruits became prized for the delectability and nutrition of their seeds, like the common pumpkin.

But when it comes to gourds, the tough little bastards have traditionally served a more utilitarian purpose. The bottle gourds of genus Lagenaria , for example, make excellent water carrying vessels—so humans artificially selected these fruits to have longer stems for handles and larger bases for bigger payloads. The stiff rind of Lagenaria can also be carved into spoons, vases and even musical instruments .

Accounts from the 1800s suggest that Native Americans of the Choctaw and Chickasaw tribes used long-necked gourds as bird houses for wild purple martins. Historians suspect the birds provided insect control for the human settlements, or perhaps the tribes simply liked having the singing passerines around. In any event, the practice spread to other tribes and then to European colonizers and, remarkably, continues to this day . In fact, the purple martins of the Eastern United States have become so reliant on gourd homes that they have completely forsaken the wild tree cavities they used to nest within.

The more eccentric decorative gourds may have originated as rejects of the edible varieties, but these days, the runts are steadily gaining in popularity. “Modern cultivated varieties are the result of very deliberate and intensive selection pressure from plant breeders,” Merrick says.

For farmers, breeding for novelty has paid off. Between 1993 and 2007, prices for decorative gourds doubled , and in 2016, the world collectively grew more pumpkins, squash and gourds than corn or mushrooms.

Despite the variety of shapes and colors, the most common decorative gourds belong to one species. If the gourds anchoring your Thanksgiving spread don’t have long necks—which is the hallmark of the water-carrying genus Lageneria —odds are the fruit belongs to the species Cucurbita pepo, Merrick says . All those little flower-printed daisy gourds ? C. pepo. Tennessee dancing gourds that look like teardrop-shaped watermelons? C. pepo. Jack-o-lantern pumpkins? Yep, those are C. pepo , too.

These cultivated gourd varieties (or cultivars) are to the Cucurbitaceae family as dogs are to wolves. A chihuahua and a great Dane are both from the species Canis familiaris , but their physical appearance has been warped by countless generations of selective breeding. For the same reason, you see drastic variation across the species C. pepo , which can be as small as nest egg gourds , slid under hens to trick them into thinking you didn’t just snatch their offspring, to world-record-setting pumpkins that weigh twice as much as a polar bear .

From beverage holders and bird homes to foodstuffs and festoons, it’s possible that even the cultural phenomenon of decorative gourd season has underestimated the value of these curious and versatile vessels.

“I’m not researching Cucurbits anymore,” Merrick says, “but I lived and breathed them for a really long time and still feel really passionate about them.”

It’s that time of year, so don some flannel, grab a hot cup of pumpkin spice tea—perhaps steeped in a calabash container —and feel free gourd your heart out.