Strobilanthes is a genus of perennial flowering herbs and shrubs with about 250 species, at least 46 of which are native to India. All species are native to Asia, with most growing in tropical regions. Many species are cultivated for their attractive flowers or foliage, and many are kept as houseplants. While some Strobilanthes species bloom yearly, others are plietesials, meaning they grow without blooming for several years, then produce a great quantity of flowers, release seeds, and die. The cycle can be from eight to 16 years long, depending upon the species.
Strobilanthes wallichii or Strobilanthes atropurpureus, commonly called Hardy Persian Shield, Kandali, Kashmir Acanthus, or Wild Petunia, is native to the Himalayas. In the wild, its purple flowers bloom only once every 12 years, an event celebrated in the Kandali Festival in the Pithoragarh district of India. The festival also commemorates the defeat of Zorawar Singh's army in 1841, which took place when the Kandali were in bloom. During the festival, women ritually destroy the plants, where the invading soldiers hid according to legend. This ceremony is followed by a victory dance and feasting.
Strobilanthes callosus, commonly called Karvy or Maruadona, grows on the west coast of India. Its bright purple flowers bloom once every eight years, between July and September. The blooming season draws a large number of pollinators, including butterflies, birds, and bees. After the flowers die, the shrub is covered with fruits, which become dry by the following year. With the first rains of the year, the dried seed pods absorb moisture and pop audibly, dispersing their seeds to grow in the wet soil.
The thick, dark honey produced by bees from S. callosus nectar is a local delicacy. The leaves of the plant are poisonous, but are used in folk medicine to treat inflammatory ailments and gastrointestinal disorders. The leaves are also used as thatching for huts.
Strobilanthes kunthiana, or Neelakurinji, is native to South India. Its purplish blue flowers bloom once every 12 years. A mountain range of the area is named Nilgiri, meaning "blue mountains," in reference to the flowers.
Strobilanthes dyerianus, native to Myanmar, is commonly called Persian Shield and is prized for its interesting foliage, dark green with metallic purple stripes radiating out from the center of the leaf. It also produces pale purple blooms, though rarely. S. dyerianus is one of the most commonly cultivated Strobilanthes species.