Odontonema callistachyum is a large tropical shrub with showy purple flower spikes all winter long. An inflorescence consisting of scores of tubular flowers develops at the tip of nearly every branch, providing an extended period of bloom. The flower spikes can reach nearly a foot long when fully developed. Hummingbirds and butterflies are attracted to the inch-long blooms if they are in residence at the time of year when flowers are open.
The stems are herbaceous, becoming slightly woody at the base. The plant grows up to 8 feet tall and wide but can be kept pruned to about half that size. The growth habit is somewhat sprawling, so a little trimming back is usually required anyway. Pruning also forces additional branching and therefore more flowers. I usually do a final pruning in late summer so that new growth has a chance to mature before the initiation of flower spikes.
The leaves are large and give a tropical look to the landscape even when the plant is not in bloom. Individual leaves grow up to 8 inches long and nearly as wide.
Odontonema callistachyum is native to Mexico and Central America. It is recommended for USDA Zones 9 to 11. In colder pockets of Zone 9 the flowering season is often cut short by frost or freeze. In these areas it can be grown as a perennial shrub. It will flower in containers, but requires diligent pruning to keep it from becoming tall and lanky.
Flowering is best in full or half-day sun, but the foliage looks best if given a little shade during the summer.
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