Autumn has become synonymous with “pumpkin spice.” You can find pumpkin spice lattes, breakfast cereal, cookies, candies, and seemingly every other type of pre-packaged food available.
But what exactly is pumpkin spice, botanically speaking?
The flavors most associated with “sweater weather” are actually a blend of spices from tropical plants.
The five most common spices used in recipes for pumpkin pie spice are cinnamon, ginger, nutmeg, cloves, and allspice. All of these spices come from different plants—and different parts of those plants—that have their own unique flavors, aromas, uses and histories.
Learn more about these plants that give fall its sweet and spicy flavor with the below information from the Missouri Botanical Garden’s Kemper Center for Home Gardening.

Cinnamon
Scientific name: Cinnamomum spp.
What part of the plant is it? The dried bark of a number of tree species in the Cinnamomum genus are called “cinnamon” and used in cooking.
Where is it from? C. verum (Ceylon or true cinnamon) is native to Sri Lanka.
More about the plant: True cinnamon has a delicate flavor with floral notes. It is sometimes sold as Mexican cinnamon and is the traditional choice to flavor mole, horchata, and other culinary delights. Most Americans grew up eating cinnamon rolls and French toast made with what is called cassia cinnamon. When sold ground, it is often a mix of different closely related species including C. burmannii (Indonesian cinnamon) and C. cassia (Chinese cinnamon). The flavor notes are more pungent and spicier than Ceylon cinnamon.

Ginger
Scientific name: Zingiber officinale
What part of the plant is it? This tropical plant has a fleshy rhizome that has been used as a cooking ingredient and medicinal herb for millennia.
Where is it from? Zingiber officinale’s Native range is in tropical Asia.
More about the plant: Its flavor is warm and spicy with vegetal notes. Ginger is fairly easy to grow from rhizomes purchased at the grocery store. Try to find rhizomes that are plump and firm, ideally with buds or eyes that are already swelling and showing signs of new growth.
DIY: In St. Louis, ginger plants can be grown in large containers and overwintered indoors. Once the rhizomes have reached the desired size, a portion of them can be harvested, leaving the rest in the container to regrow.

Nutmeg
Scientific name: Myristica fragrans
What part of the plant is it? Seeds are processed to remove their outer seed coat. The inner kernel is what we know as the spice nutmeg.
Where is it from: This tropical tree is native to only a few islands in eastern Indonesia known as the Maluku Islands, but today is grown in tropical regions around the world. Freshly harvested nutmeg seeds are dark brown with a bright red, web-like outer covering called an aril.
More about this plant: Ground nutmeg has a distinctive nutty, woody, and sweet flavor. It can overwhelm other flavors, particularly if freshly ground, and so most recipes call for less of it than ginger and cinnamon. The aril is the source of the culinary spice mace.

Clove
Scientific Name: Syzygium aromaticum
What part of the plant is it? The ground or whole spice used in cooking is the dried, unopened flower bud of the clove tree.
Where is it from? Like nutmeg, clove is a tree native only to the Maluku Islands of Indonesia but is now grown commercially in tropical areas of other countries including Madagascar, Tanzania, and Sri Lanka.
More about this plant: The flavor is sharp and intensely aromatic, with woody, fruity, and sweet notes. A little goes a long way, and most pumpkin pie spice recipes require only a small amount of clove.

Allspice
Scientific name: Pimenta dioica
What part of the plant is it? Allspice is the dried unripe fruit of a small tree.
Where is it from? Pimenta dioica is native to Central and South America.
More about this plant: Allspice is an important part of many Caribbean dishes. It is often assumed to be a blend of different spices given its name. However, the name comes from its flavor, which is similar to a mix of cinnamon, nutmeg, clove, and black pepper. Like clove, allspice can be overpowering and most pumpkin pie spice recipes only include a little bit.
Justina Kandra
Horticulturist, Kemper Home Gardening Programs
Catherine Martin
Public Information Officer
Photo credits: Ehoarn Bidault, Idris Abdul Haris, David Stang, Indiana Coronado Tropicos, Missouri Botanical Garden Plant Finder