Which plant species must be used to make tequila under Mexico’s official rules?

Tequila must be made from Blue Weber agave, scientifically known as Agave tequilana Weber var. azul, under Mexico’s official tequila rules.

The plant is a blue-gray agave with thick, pointed leaves. Producers harvest its underground heart, called the piña because it resembles a pineapple. The piñas are cooked, crushed, fermented, and distilled to make tequila.

Other agave species are used for mezcal, including the widely used Espadín agave. That is why tequila and mezcal are related but not interchangeable categories. Tequila production is restricted to defined Mexican regions and follows a protected denomination of origin.

Blue Weber agave generally takes several years to mature before harvest. It is not a cactus, although its spiny appearance often causes that mistake; agaves are succulent plants in the asparagus family.