The tomatillo (Physalis philadelphica) is a plant of the nightshade family, related to the Cape gooseberry, bearing small, spherical and green or green-purple fruit of the same name. The tomatillo is also known as the husk tomato, jamberry, husk cherry, or Mexican tomato, but the latter is more appropriately used to describe a relative which bears smaller fruit. Tomatillos originated in Mexico, and are a staple of that country's cuisine, most notably as the key ingredient in salsa verde. They are grown as annuals throughout the Western Hemisphere. Tomatillos are frequently eaten fried, boiled, or steamed.
The tomatillo fruit is surrounded by an inedible, paper-like husk formed from the calyx. As the fruit matures, it fills the husk and can split it open by harvest. The husk turns brown, and the fruit can be several colors when ripe, including yellow, red, green, or even purple. Tomatillo plants are highly self-incompatible, and two or more plants are needed for proper pollination.