Agave guadalajarana aka Guadalajara Agave

Agave guadalajarana is an evergreen succulent in the asparagus family. It comes from western Mexico, including Jalisco and Nayarit. It grows on rocky volcanic slopes among grasses and oaks. Some sites also have pine trees. Its home range has a long dry season. Useful Tropical Plants reports an Endangered listing from 2019. Collectors remove wild plants, while spreading suburbs reduce its habitat.

The plant forms a dense rosette with no visible stem. Most plants stand alone, though some make a few offsets. Garden rosettes reach about 0.8–1.6 feet [0.25–0.5 metres] tall. They spread about 1.1–3.3 feet [0.35–1 metre] across, depending on the source. Broad, stiff leaves give the plant its rounded shape. Their colour ranges from grey-green to pale blue-grey. Packed young leaves press lasting marks into their neighbours. Large teeth line the edges and grow larger near the tip. Each leaf ends in a stout brown spine.

Growth is slow, and flowering takes many years. The RHS gives a maturity range of 10–20 years. The flower stalk rises far above the low rosette. Sources place it at 9.8–16.4 feet [3–5 metres] tall. Its upper branches carry groups of small yellow flowers. Hummingbirds pollinate them, according to Useful Tropical Plants. Thick-walled capsules have three chambers and hold crescent-shaped seeds. The main rosette dies after it flowers. Any offsets can keep growing after that loss.

Give this agave full sun and soil that drains well. The RHS lists sandy or loamy soil with acid to neutral pH. LLIFLE also allows light shade. Water well during growth, then let the soil dry. Keep it almost dry through winter. The RHS rates it H2 and calls for frost-free winter shelter. LLIFLE suggests much greater cold tolerance, but labels that claim uncertain. A greenhouse or conservatory suits the RHS guidance. Pots allow a sunny summer stay outdoors. Its compact form also suits gravel beds and courtyard displays where conditions permit.

Scale insects may attack, but the RHS reports few disease problems. The plant needs no pruning. Grow new plants from seed or remove offsets in spring or autumn. Wear gloves when handling its sharp leaves; the plant can irritate skin. It also harms cats and dogs if eaten. People use harvested plants to make mezcal. Useful Tropical Plants records medicinal use but gives no treatment details. These uses do not establish that raw plant parts are safe to eat.