Common Name: coastal agave
Type: Herbaceous perennial
Family: Asparagaceae
Native Range: Southern California, northwestern Mexico
Zone: 9 to 10
Height: 2.00 to 3.00 feet
Spread: 3.00 to 4.00 feet
Bloom Time: February to May
Bloom Description: Yellow-green
Sun: Full sun
Water: Dry
Maintenance: Low
Flower: Showy
Leaf: Evergreen
Attracts: Hummingbirds, Butterflies
Other: Thorns
Tolerate: Deer, Drought, Dry Soil, Shallow-Rocky Soil
Culture
Best grown in dry, rocky to sandy, well-draining soils in full sun. Do not provide supplemental irrigation once established. Hardy in Zones 9b(25°F)-10.
Noteworthy Characteristics
Agave shawii, commonly called coastal agave or Shaw's agave, is a succulent, herbaceous perennial native to coastal sage scrub and chaparral along the Pacific coast of Baja California and southern California. Mature rosettes will reach up to 3' tall with a 4' spread. Clumps will spread by offsets to form small colonies. The upright, ovate leaves can reach 20" long and 8" wide with sharp, hooked, red spines along their margins and a stiff terminal spine reaching up to 1.5" long. From late winter into early summer, a single, 8-12' tall flowering stalk will emerge from the center of rosettes that are 15-30 years old. The flowering stalks are topped with a branched panicle made up of dense clusters of 3.5-4.5" long, yellow-green, tubular flowers. The rosette will dieback after blooming. The flowers are attractive to hummingbirds, butterflies, and other pollinators. This plant is a larval food source for the California Giant-Skipper, a butterfly species endemic to southern California.
The genus name Agave comes from the Greek word agauos meaning "admirable" or "noble" in probable reference to the very tall flower spikes found on the plants of many species of Agave.
The specific epithet shawii honors Henry Shaw (1800-1889), English-born American philanthropist, businessman, and founder of the Missouri Botanical Garden in St. Louis, Missouri.
Problems
No major pest or disease problems of note. Overly wet or heavy soils will lead to root or stem rot. This plant has very sharp marginal and terminal spines. Handle with care.
Uses
Suitable for xeriscaping, desert gardens, rock gardens, and seaside gardens. Typically forms spreading clumps. This plant has very sharp marginal and terminal spines. Handle with care and do not situate near sidewalks, driveways, or other highly trafficked areas.