While tomatoes and tomatillos often appear similar, they are distinct plants with unique characteristics. Many people encounter small, green, husk-covered fruits and might mistake them for unripe tomatoes, but these are typically tomatillos. These two fruits offer different flavors and culinary applications. Understanding their botanical connections and individual attributes clarifies their true identities.
A Shared Heritage: The Nightshade Family
Tomatoes (Solanum lycopersicum) and tomatillos (Physalis philadelphica or Physalis ixocarpa) are both members of the Solanaceae family, commonly known as the nightshade family. This shared family lineage indicates a common evolutionary origin.
Plants within the Solanaceae family exhibit similar structural characteristics. They typically possess bisexual flowers with five fused petals and five sepals. The fruits of many nightshade plants, including tomatoes and tomatillos, are botanically classified as berries. This family also includes other food crops such as potatoes, peppers, and eggplants.
Beyond Kinship: Distinctive Traits
Despite their shared family, tomatoes and tomatillos display notable differences in appearance, flavor, and culinary uses. Tomatoes come in a wide array of sizes, shapes, and colors, from red to yellow, orange, pink, and even purple. Tomatillos are typically small, spherical, and bright green, though some varieties can ripen to yellow or purple. A distinguishing feature of the tomatillo is its papery, inedible husk, which completely encloses the fruit as it develops. This husk turns brown and often splits open as the fruit matures.
Their flavor profiles are also distinct. Tomatoes are known for their balance of sweetness, acidity, and savory umami notes. Tomatillos, especially when raw, offer a tart, bright, and slightly citrusy flavor with an earthy undertone, often described as more acidic than tomatoes. When cooked, tomatillos tend to become milder and sweeter.
These flavor differences dictate their primary roles in cooking. Tomatoes are versatile, used fresh in salads and sandwiches, or cooked into sauces for pasta and pizza, soups like gazpacho, and various condiments. Tomatillos are a staple in Mexican cuisine, most famously as the base for vibrant salsa verde. They are also incorporated into stews, soups, and even jams, benefiting from their high pectin content which helps thicken sauces.
Growing habits also set them apart. Tomato plants typically grow as vines that can reach significant heights, often requiring stakes or cages for support. Tomatillos also exhibit a sprawling, vine-like growth, often needing trellising or caging. Tomatillo plants require cross-pollination, meaning at least two plants are needed for successful fruit production.