Agave havardiana
Native range: Trans-Pecos region of Texas and northern Mexico
Known names: Havard Agave, Century Plant
Hardiness: USDA Zone 5 (-20 to -10°F) to 11, exceptionally cold-hardy.
Mature Size: 2'-3' tall, 3'-5' wide (moderate grower, typically adding 2"-4" per year)
Light: Half day direct sun, full sun
Water: Allow soil to dry completely between waterings; drought tolerant, water more often during hot months
Soil: Extremely well-draining, gritty cactus and succulent mix.
Dormancy Period: Winter
Pet-Safe: No
Plant Size: Grown in 4" pot, shipped bare root.
 
Robust and striking, Agave havardiana forms a large, open rosette of broad, powdery blue-gray leaves heavily armed with dark marginal teeth and a sharp terminal spine. It produces a massive, towering central stalk bearing greenish-yellow flowers after many years of growth, after which the main rosette dies. In cultivation, it requires a site with bright direct sunlight and an extremely well-draining, gritty succulent soil. Ideally grow this plant as a container specimen or in arid rock gardens, as it tolerates extended drought once established. Its species name havardiana honors Dr. Valery Havard, a 19th-century military surgeon and botanist who documented the plants of the American Southwest.