Pteracanthus

Strobilanthes is a genus of about 350 species of flowering plants in the family Acanthaceae, mostly native to tropical Asia and Madagascar, but with a few species extending north into temperate regions of Asia. Many species are cultivated for their two-lipped, hooded flowers in shades of blue, pink, white and purple. Most are frost-tender and require protection in frost-prone areas. The genus is most famed for its many (but not all) species which bloom on long cycles of several years, such as Strobilanthes wightii which blooms every thirteen years.