Agave is a genus of flowering succulent plants containing more than 136 identified species and cultivars. Agave plants thrive in arid and desert conditions on little water or external nutrients. Instead they store moisture in their fleshy, and sometimes spiked, leaves. According to Scott Kress from San Francisco State University, agave plants live for up to 12 years and die after the plant blooms just once. Oddly, this feature categorizes agave as an annual plant, even though it is a relatively long-lived succulent. Cultivated agave plants bloom even less frequently than plants in the wild, often exceeding the normal lifespan of the species. Several species of agave are used in making the popular alcoholic libation tequila, primarily from cultivars of the blue agave.
Look for succulent plants growing in sub-tropical to arid desert climes in dry, poor soil conditions that are commonly sandy, rocky or gravel laden. The skin of the plant will appear slightly dusty with a whitish wash over hues of blue, green or purple. The leaves will be solid in color, variegated or have an ombre--faded gradation of color.
Identify agave species plants in a range of sizes from 2 feet high to upward of 7 feet high and 12 feet in spread. All agave will be round in overall form and roughly symmetrical, save for any damage to the plant that may alter the natural shape.
Look for succulents with tick fleshy leaves shaped in a soft, elongated triangle and coming to a sharp, fine point at the outermost tip. All new leaves appear to emerge from a central rosette or eye surrounded by slightly overlapping layers of older larger leaves that spread out and slightly down over time.
Locate agave plants by their large vertical flower stalks that rise up through the center of the succulent like a spire. The flower stalks often dwarf the plant and can grow to 30 feet high. The stalk produces yellow blooms in horizontal stems, and the entire flower head structure can grow to 6 feet in diameter. when mature. Flowering agave can be identified as plants that are 10 years or older--younger plants cannot produce the bloom.