Tropical Surprise for Winter

Two years ago, I ran into (literally) a stand of 6-foot tall (2 m) Persian Shield [22.9.2009] (Strobilanthes dyerianus) plants at the Atlanta Arboretum. I was impressed with this hedge enough to research their use as a decorative hedge in my back yard. I soon discovered that growing this tropical plant in Virginia as an annual means a maximum height of only 3 feet (1 m) during the summer. I will guess that the arboretum used some super fertilizer or took advantage of their greenhouse.

However, in my research, I discovered that the plant is noted for easily rooting from cuttings. I started a few plants from fall cuttings, and kept the 2-inch high (5 cm) plants alive on a winter windowsill until spring let me plant them outdoors. The purple color disappears in the winter as leaves turn green, but the intense purple comes back when planted outdoors in the spring. Last summer, the two survivors grew well.

This year, I started a few more in autumn with the hope of getting them to actually grow in the winter, and to give them a healthier head start when transplanted outdoors this spring. Much to my surprise, one of them just started blooming. With the plant only 4-inches tall (10 cm), the flowers arrived. They are not fragrant or extremely large. Still, how many gardeners can actually say their strobilanthes bloomed?

The pots are on an east facing window sill receiving morning sun in a room that is not heated. I must assume the plant flowers in the winter in its native habitat, when weather is cooler and/or days are shorter. One web site states the plant blooms in spring and early summer, while another gives fall as bloom time. Maybe I should report "winter" blooming, so that all seasons are covered and really confuse the heck out of amateur gardeners like myself.

For The Record:   • Indoors: Unheated second floor room of the house   • Indoors: Full sun on windowsill for 2-3 hours   • Outdoors: Mostly shade, moist soil   • No fertilizer