Agave parryi - Artichoke Agave
Artichoke Agave is native to the Southwest United States and Mexico. A compact succulent known for its stubby, almost flat-topped rosettes, it's reminiscent of an artichoke. Each leaf has a sharp 1" spine at the end, but the plant doesn't flop out into walkways and threaten your ankles. It makes a fine container plant and a handsome specimen in a desert garden.
Individual plants grow slowly to 2' tall by 3' wide. This is one of the cold hardiest of the agaves and will grow in drier areas of Zones 5-11. Propagate by seed or removing offshoots from the base in spring. The 20' bloom is a sight to behold, though you may not see one for a couple of decades. In the meantime, this is one great-looking plant.