Tecoma stans is a yellow flowered shrub or small tree that blooms throughout the warm months of the year. The trumpet-shaped flowers are two inches in length and nearly two inches across. Branched flower spikes are clustered on the ends of new growth, and hold several dozen buds that open in succession. The blooms have a light fragrance up close, and attract Sulphur butterflies.
Leaves are pinnately-compound with serrated margins.
This species comes in several different varieties. Tecoma stans var. stans, known as common yellow elder, grows up to 25 feet tall with multiple trunks. It is native to Central and South America, and is evergreen or semi-deciduous, depending on the winter temperature. It is reliably hardy to around 28°F, but will come back from the roots after temperatures in the low 20s F. This is the variety pictured here. At 26°F, mine are semi-deciduous, with no dieback in slightly sheltered locations. The plant has a somewhat open growth habit, but shrubs can be kept pruned for a fuller appearance.
Arizona yellow bells (T. stans var. angustata) comes from the Chihuahuan Desert in Texas and New Mexico. It is a deciduous shrub that grows to 10 feet in height, and is hardy to 10°F. It can be grown as a perennial as far north as USDA Zone 7. 'Gold Star Esperanza' is a cultivar that is grown as an annual and reaches three to four feet in height.
Flowering of all varieties is best in full sun, and the plants prefer a well-drained location. In South Florida, T. stans will sometimes naturalize in dry areas. It is considered invasive on some Pacific islands.