Alula, Cabbage on a Stick | San Diego Zoo Animals & Plants

San Diego Zoo Animals & Plants

Endangered

Brighamia insignis

CLASS: Magnoliopsida
ORDER: Asterales
FAMILY: Campanulaceae (Bellflowers)
GENUS: Brighamia
SPECIES: insignis

OVERVIEW

Possibly one of the strangest looking plants, a full head of succulent leaves crowns from the top of a stem. This is one of the rarest plants in the world, at least in the wilderness. Many steps have been taken to try and propagate it so that it can be reintroduced back to its native habitat in Hawaii.

A single alula surrounded by a ring of lava rocks grows on a grass lawn in Hawaii.

CHARACTERISTICS

This perennial usually only reaches 3 to 6 feet in height—but some can reach 15 feet tall! The succulent stem is bulbous at the bottom, tapering upward to a top-knot of fleshy, spoon-shaped leaves arranged in a rosette pattern.

Clusters of three to eight fragrant yellow flowers bloom from September to November, and are said to smell similar to honeysuckle; others describe the scent as citrus-like. The trumpet-shaped flowers are impressive, with petals fused into nearly 6-inch-deep tube.

CONSERVATION

Alula growing amongst moss covered lava rocks in the Hawaiian garden at the San Diego Zoo. — Alula can be found growing in the San Diego Zoo's Hawaiian garden.

Once found only on a few cliffs on the island of Kauai and Niihau, this plant owes its very survival to some extremely dedicated botanists. The natural pollinator of the alula, a type of hawk moth, has become extinct—hampering the plant's ability to reproduce.

When the numbers of alula began decreasing, botanists in Hawaii started rappelling down the steep cliffs where the plant is found to hand-pollinate the last remaining individuals. Later, they returned to collect the seeds that were later grown in a greenhouse. Today, the "cabbage on a stick" plant is found in plant conservatories around the world, and is even available in nurseries and mail order catalogs.