Agave plants (Agave L.), using their iconic leaves and striking appearance, bring a dramatic existence and include a bold, geometrical nuance to landscape design at the American Southwest. Hardy at U.S. Department of Agriculture plant hardiness zones 5 through 11, agaves are ideal for the extremely arid conditions of the desert, having hard, spiny exteriors that protect their highly hunted moisture from natural predators. Although agaves share intrinsic attributes common to all succulents, like dense fleshiness and swollen leaves, several different features set them apart from other plants within their classification.
Examine the arrangement of the leaves close to the succulent’s foundation to get a rosette pattern. A rosette refers to a layered, circular arrangement of leaves or petals arising out of a stem to protect the plant. Rosettes on succulents like agaves result from short internodes, the part of the stem between two leaf nodes.
Search for thick, stiff symmetrical leaves ranging in shade from blue-gray to blue or gray to dark-blue with spiny margins that taper to a sharp point. The dark-red or black spines growing from the leaf margins are approximately 1/3-inch long and those growing from the tips grow to about 1/2-inch long.
Notice whether the form of the leaves fit the agave profile, which typically climb broad, long and slender or shaped like a spear.
Remove a leaf from the succulent, bisect it using lopping shears and examine its interior for moist, fibrous tissue running throughout. Just like succulents, the fibrous tissue helps the plant tolerate drought conditions by storing water.
Examine the plant to get inflorescence, a flowering construction with petals arising from a long stem, and also referred to as a mast. The agave’s mast grows a few feet from its own rosette, with a few varieties reaching a height of up to 30 feet.
Note the form and appearance of this succulent’s flowers growing from the inflorescence. Agaves grow spiked sections of yellow, cream or lime-green colored tubular flowers from their masts that develop so vigorously the plant often dies within a couple of days.
Examine the foundation of this succulent for several root suckers, called pups, growing nearby. The pups resemble little agave rosettes, and replace the plant after it dies on its own or with help from a spreading gardener.