This plant is native to south-western Australia (Queensland, New South Wales and Victoria). Its exuberant flowering of large red spikes is accompanied by a subtle citrus scent, hence the epithet "citrinus" for one of the most common species, Callistemon citrinus.
Callistemon comes from the Greek, meaning "beautiful stamens", alluding to its flowers. Among the most common species are C. rigidus (with stiff, erect branches), C. viminalis (with slender, flexible, weeping stems) and the two most common species; C. citrinus (often identified with the synonym C. laevis, from the Latin lēvis, meaning light or soft) and C. speciosus, (generally lower than C. citrinus and with narrower leaves). The main difference between these two species is their inflorescences, which are denser in C. speciosus than in C. citrinus, with yellow rather than red anthers, and a style slightly longer than the stamens.
Most of these species were described rather late, in the early 20th century, but they are quite widely used in gardening for their rapid growth, luxuriant flowering and adaptability.