Agave americana aka Agave

Agave americana, or century plant, is an evergreen perennial succulent. It belongs to the asparagus family, Asparagaceae. Its native range runs from the southern United States into Mexico. Growers have planted it in many other warm regions. It has escaped gardens and formed wild stands abroad. The plant grows slowly and forms clumps through basal offsets.

Its thick leaves form a rosette with no visible stem. They range from blue-green to grey-green and have sharp edges. Each leaf ends in a strong, pointed spine. Leaves can reach 6 feet [1.8 metres] in length. Garden size varies greatly with the source and growing conditions. RHS gives about 3–5 feet [1–1.5 metres] for height and spread. NC State gives 6–10 feet [1.8–3 metres] for both dimensions. Plants stay much smaller when grown indoors in pots.

The name does not mean it needs a century to bloom. A plant may take 10–25 years to produce flowers. Its thick flower stalk rises 15–30 feet [4.6–9.1 metres], sometimes higher. Branches near the top carry panicles of greenish-yellow, tubular flowers. Reports place bloom in May and June or summer. Bats pollinate the flowers, which have a musky scent. The main rosette dies after bloom, while offsets grow near its base. Gardeners can raise new plants from offsets or seeds.

Outdoors, it needs full sun and soil that drains well. Sandy soil suits it, though other well-drained soils also work. Established plants cope with drought, dry soil, and salt. It suits rock gardens, slopes, and gardens with little water. Its bold leaf form gives gardens a focal point year-round. Missouri Botanical Garden lists USDA zones 8–10; other sources extend that range. RHS rates it H2 under UK conditions, where it needs frost protection. Under glass, use cactus compost and bright, filtered light. Water during growth, but keep it nearly dry through winter.

Wet soil can cause root rot. Agave weevils, scale insects, slugs, and snails may cause damage. Most plants have few serious pest or disease problems. The sap can irritate human skin and contains calcium oxalate crystals. Dogs and cats may suffer harm if they eat it. Wear gloves when handling plants, and allow space around their spines. Reported food uses include baked hearts, roasted flower stalks, and ground seeds. People also use the sap for syrup and fermented drinks. Other uses include fibre, soap, erosion control, and boundary planting.