Ruellia californica aka Ruellia Californica

Ruellia californica is a perennial evergreen shrub in the family Acanthaceae, native to the arid Baja California peninsula and adjacent coastal Sonora in northwestern Mexico. It typically grows to about 1.5 m (4.9 ft) tall and produces small ovate to lanceolate or elliptic leaves on woody, branched stems. Two subspecies are recognized: subsp. californica, which bears glandular trichomes on its foliage, and subsp. peninsularis, endemic to Baja California Sur, which has smooth, glossy, somewhat sticky leaves without trichomes.

The plant is best known for its showy funnelform flowers, which are 3–5 cm (1.2–2.0 in) long, blue-purple in color, and marked with yellow in the throat. Each flower has a five-parted calyx and four stamens. In its native range it can flower nearly year-round and is often one of the only plants in bloom during dry parts of the year, an indication of its remarkable drought tolerance. The fruits dehisce explosively when wetted, ejecting and dispersing the seeds.

In the wild, R. californica grows on dry, gravelly slopes, bajadas, hillsides, rocky washes, arroyos, and canyons — habitats characterized by intense sun, sparse rainfall, and well-drained mineral soils. These conditions translate directly to its cultivation requirements: full sun, fast-draining soil, and minimal supplemental water once established. It is grown as an ornamental shrub to provide a long season of color in desert and dry gardens, where its compact habit and persistent blooms make it a useful accent plant.

The species was first described as Calophanes californica by Vasey and Rose and transferred to Ruellia by Ivan Murray Johnston in 1924; both Calophanes californica and Calophanes californicus are recognized synonyms.