Future Plants by Randy Stewart: Persian Shield

Saturday, February 4, 2012

Persian Shield

Strobilanthes

A genus of tropical perennials that are part of the larger Acanthaceae family.

Strobilanthes atropurpurea ( Hardy Persian Shield )
Also called Strobilanthes wallichii or Ruellia alata. An upright, large, clumping perennial, reaching up to 6.5 x 4 ( rarely over 5 ) feet in height, that is native to the Himalayas from Pakistan to China; south into southeast Asia.
The toothed, ovate to elliptical leaves, up to 6.5 x 2.5 inches in size, are luxuriant mid-green.
The bluish-purple, tubular flowers, up to 2 inches in length, are borne on dense spikes during mid-summer to mid-autumn.
Hardy zones 5 to 11 in full sun to partial shade on fertile, very well drained soil.

Strobilanthes dyerianus ( Persian Shield )
A tropical shrub, reaching up to 10 feet, that is native to Burma. Outside the tropics, it is grown as a perennial, reaching up to 6 x 5 feet, in zone 9. It is also used as a fast growing annual in temperate climates that is planted outside after the risk of frost has passed. An an annual, it will rarely exceed 3 feet in size.
In temperate climates it is most commonly seen in patio containers, mixed with blue or white flowering trailing plants.
The Persian Shield is very commonly seen in the U.S. in south Florida.
The thick leaves, up to 10 inches in length, are deep blue-green and richly variegated with bright purple. The foliage is solidly bright purple beneath.
The flowers are pale purple but rarely occur outside the tropics.
It thrives in partial shade on moist, fertile, humus-rich, well drained soil.
It is not tolerant of road salt or ocean salt breezes but is otherwise easy to grow anywhere summers are sufficiently hot and humid. As a perennial, it is only hardy to the 20s or on a very protected site 18 F.

* photo taken on Aug 25 2011 @ Scott Arboretum, Swarthmore College, PA