Vanilla orchid is a common name that refers to the vine-like evergreen plants in the genus Vanilla, belonging to the Orchidaceae, or orchid, family. These plants are rooted in the ground but may also climb tree trunks, poles, or other means of vertical support. Upon maturity, the vines can reach lengths of 115 feet (35 m) or more. There are at least 100 species of these plants, which are mostly found in tropical and subtropical regions in the Americas, Africa, and southeast Asia. They are also grown in the western Pacific Islands.
These plants receive their name from the Spanish word vainilla, which means little pod or capsule, in reference to the plant's long, pod-like fruits, commonly referred to as vanilla beans. Measuring 4 to 10 inches (10 to 25 cm) long, these fruits contain small seeds that ripen eight to nine months after flowering. An identifying characteristic of these plants are the roots that sprout on the stem. Aerial roots are slender and smooth, while those that contact the surface have a thick and shaggy appearance. Vanilla orchid plants have green leaves that are short, thick, and leathery.
The white, green, or cream flowers of the vanilla orchid typically grow upside down. These large and showy flowers are ephemeral, meaning they are short-lived. They open in the morning and close in the afternoon. If no pollination occurs when the flowers are open, they shed the next day. Pollination in the wild is done by bees and hummingbirds, whereas commercially grown species must be hand pollinated.
Due to its high vanillin content, the species V. planifolia is thought to have the highest commercial value amongst the cultivated vanilla orchid plants. Derived from the extract of its seedpods, vanillin is the source of vanilla flavoring widely used in food preparation and perfumes. Vanilla plants reportedly have medicinal uses, such as a remedy for fevers and as an aphrodisiac, though these claims have not been scientifically proved.
V. pompona and V. tahitiensis are other vanilla orchid species commercially grown for vanillin extraction. Their vanillin content is lesser than that of V. planifolia, however. Other species of interest are V. dilloniana, V. mexicana, and V. phaeantha due to their inclusion on lists of threatened and endangered plants in some regions of the United States. All species within this genus are a food source for species within the Lepidoptera order, which contains thousands of moths and butterflies.