Scientific: Agave nickelsiae (formerly Agave x ferdinandi-regis)
Common: King agave, King of the agaves, King Ferdinand Century Plant, Nickels' agave
Family: Asparagaceae (subfamily Agavoideae)
Origin: Mountainous region northeast of Saltillo, northwestern Mexico
Pronounciation: A-GA-ve nic-kel-SIGH-ae
Hardiness zones:
Sunset 12-24
USDA 9-11
Landscape Use: This is a smaller agave for more personal landscape spaces, small residential front yards, succulent collection gardens, textural accent, great for night lighting and night-time textural effects (here is an image of night lighting of king agave.
Form & Character: Small, upright, slowly open rosetting, stiff, stout, regal.
Growth Habit: Evergreen, succulent, succulent perennial, monocarpic (flowers after about 20 years), mildly fibrous, very slow growth rate strongly open rosetting habit. Produces occassional off shoots from underground rhizomes.
Foliage/Texture: Stout, triangular, glaucous blue-green leaves with pronounced longitudinal narrow white bud inprints, leaf margins are spineless, dark reddish-brown, leaf apex is a blunt tip with a short stout blackened spine; medium coarse texture.
Flowers & Fruits: Strong flower stalk to 10- to 20-feet tall (amazingly tall flower stalk for such a small plant), spiked-shaped inflorescence , flowers paired, 2 inches long, petals 'fanning' out widely at the mouth, stamens extend beyond the petals, flower color off white to mostly purple red; fruits are a capsule.
Seasonal Color: None
Temperature: Mostly tolerant of desert heat, hardy to 20oF.
Light: Full sun, except will look a little less stressed in Phoenix with a few hours of protection from the extreme summer western sun.
Soil: Tolerant
Watering: Limited to no supplemental irrigation is required for king agave agave. Irrigation will increase vigor somewhat.
Pruning: None
Propagation: Division of underground rhizomes.
Disease and Pests: None
Additional comments: If you're a small agave collector like me, then king agave is one you have to have in your display garden or front yard landscape for all to see. It's totally awesome and people friendly. Sharkskin agave is a hybrid of king agave and Agave scabra.
Taxonomic confusion: The taxonomic history of the king agave is a bit confounded. It was first named Agave nickelsiae in 1895, but was renamed in 1915 by Berger as Agave ferdinandi-regis. Later Gentry proposed that it was only a form of Agave victoriae-reginae. More recently it has been renamed Agave nickelsiae due to its unique floral character.
