Blue Weber Agave is the cultivated species of Agave plant used to make Tequila. Blue Weber Agave is the ONLY agave legally allowed to be used in the production of Tequila. The plant is named after botanist who was credited for deciding it was the best Agave plant for the production of Tequila. This variety of Agave was picked due to its high production of sugars, mostly fructose, in the heart or "piña" of the plant.