How To Differentiate A Pumpkin From A Squash

Pumpkins, squashes, melons, cucumbers and summer squashes are all part of a larger family referred to collectively as the cucurbitae. These are vining plants that produce large fruits called pepos, with a large quantity of flat seeds contained in their pulpy flesh. Pumpkins and squashes are closely related, and the difference between them often has more to do with custom than botany.

The Squash Family

The squash family in the Americas consists of five species: Cucurbita pepo, Cucurbita moschata, Cucurbita maxima, Cucurbita mixta and Sechium edule. Sechium edule and Cucurbita mixta are very small species, consisting of the pear-sized chayote and the cushaw, respectively. All true pumpkins belong to the Cucurbita pepo species, which also includes several summer and winter squashes. The remaining three species are technically squashes, though all contain individual varieties that are customarily referred to as pumpkins.

True Pumpkins: C. Pepo

According to the horticulture department at Texas A&M Extension, several characteristics can be used to differentiate between Cucurbita pepo and its siblings. The most telling distinction is the stems. The stems of C. pepo varieties, including the true pumpkins, are woody and have deep ridges. The remaining families have softer, spongier stems that have a round cross-section and aren't ridged. Zucchini, acorn squash and spaghetti squash are part of the same Cucurbita pepo species.

Cucurbita Maxima, Mixta and Moschata

Cucurbita maxima, as the name suggests, includes several of the largest squash species. Banana and Hubbard squashes often reach weights of 25 to 30 pounds, while the Atlantic Giant can grow to several hundred pounds. Atlantic Giant is usually considered a pumpkin, and is grown purely for size. It has little culinary value beyond its seeds. Cucurbita mixta is the cushaw, an elongated squash with green stripes. Cushaw is an old-fashioned favorite for making a pie similar to pumpkin pie. Cucurbita moschata is the butternut squash family, but it includes the varieties that are most often used for canned pumpkin.

Common Usage

In common usage, custom is the usual guide in deciding which fruits are pumpkins and which are squashes. Although there are exceptions, most cucurbitae are described as pumpkins if they're primarily used for baking and squashes if they're eaten as a vegetable. They are interchangeable in many recipes, though the traditional jack o' lantern pumpkins have bland and watery flesh that's not well suited for either cooking or baking.