Agave tequilana planting these shoots; this has led to a considerable loss of genetic diversity in cultivated blue agave. It is rarely kept as a houseplant, but a 50-year-old blue agave in Boston grew a stalk requiring a hole in the greenhouse roof and flowered in the summer of 2006. Tequila is made only from a specific cultivar of "Agave tequilana" called 'Weber Azul'. This cultivar is larger and blue-gray in color compared to the smaller and green normal "A. tequilana". It is a rapid grower and prolific offsetter in keeping with its agricultural advantages. Tequila is produced by removing the heart
Agave moisture from rain, condensation and dew. In addition to growing from seeds, most agaves produce 'pups' – young plants from runners. "Agave vilmoriniana" (the octopus agave) produces hundreds of pups on its bloom stalk. Agave leaves store the plant's water and are crucial to its continued existence. The coated leaf surface prevents evaporation. The leaves also have sharp, spiked edges. The spikes discourage predators from eating the plant or using it as a source of water and are so tough that ancient peoples used them for sewing needles. The sap is acidic. Some agaves bloom at a height up to