Ground cherries and tomatillos are often confused because both fruits develop inside a distinctive, papery husk called the inflated calyx. This protective, lantern-like covering turns brittle and straw-colored as the fruit ripens, creating a strong visual similarity. Despite this resemblance, they are distinct species with different growth habits, appearances, and culinary uses.
The Shared Family and Distinct Genera
The biological relationship between ground cherries and tomatillos is that of close cousins within the same botanical group. Both belong to the nightshade family, Solanaceae, which also includes potatoes, tomatoes, and peppers. This shared family classification explains the general resemblance in foliage and flower structure.
Both plants also belong to the same genus, Physalis, a name which refers to the bladder-like nature of the fruit’s papery husk. Ground cherries typically refer to species such as Physalis pruinosa (husk cherry) or Physalis peruviana (Cape gooseberry). Tomatillos are primarily cultivated species like Physalis philadelphica or Physalis ixocarpa. While they share the Physalis genus, they are different species and maintain unique characteristics.
Key Physical Differences and Identification
The physical distinctions between ground cherries and tomatillos are clear and serve as the most practical way to tell them apart. Ground cherries are significantly smaller, generally reaching the size of a marble or small cherry tomato, about a half-inch to three-quarters of an inch in diameter. They ripen to a bright golden yellow or orange color inside their husks.
Tomatillos are much larger, typically growing to the size of a golf ball or small apple, sometimes reaching over two inches in width. Their ripe color is usually a vibrant green, though purple and yellow varieties also exist. The most obvious difference is in the husk itself: the tomatillo fruit expands tightly, often splitting the husk open and filling it completely. The ground cherry fruit remains smaller and looser within a husk that turns tan and dry.
Growth Habit
Ground cherry plants tend to be low-growing, spreading, and bushy, often sprawling close to the ground, which is why the ripe fruit often drops naturally. Tomatillos grow on larger, more upright, and taller bushes, sometimes reaching three to four feet in height, requiring caging or staking for support.
Divergent Flavor Profiles and Culinary Uses
The most significant difference lies in their flavor chemistry, which dictates their distinct roles in cooking. Ground cherries are prized for their sweetness, offering a complex, tropical taste often described as a blend of pineapple, vanilla, and caramel notes. This dessert-like profile makes them ideal for eating raw, or utilizing them in sweet applications such as jams, pies, preserves, and fruit salads.
Tomatillos possess a savory and acidic flavor, which is sharp, tart, and citrusy when raw. They are generally used as a vegetable and must be cooked to mellow their intense acidity and remove a slightly sticky residue that often coats the fruit. Their primary culinary application is as the base for the Mexican green sauce known as salsa verde. The sweet-and-savory opposition in their flavors means that, despite their similar appearance, ground cherries and tomatillos are not interchangeable in recipes.