Hibiscus mutabilis 'Plena'

The name requires a brief clarification and then we can move on to the more interesting parts. Hibiscus mutabilis has been called the Confederate Rose since the nineteenth century, when it naturalized so thoroughly in the gardens of the American South that people assumed it belonged there. It does not. It belongs to Hunan Province in China, where it has been cultivated for nearly three thousand years, where it serves as the city flower of Chengdu, a city known, on account of this plant, as the City of Hibiscus, and where classical texts on materia medica describe its flowers and leaves in medicinal detail. The name stuck here out of regional habit rather than botanical or historical accuracy. The plant itself is indifferent to what we call it.

What 'Plena' actually is: a fully double-flowered cultivar of one of the most theatrically interesting shrubs available to Southern gardeners. The flowers of H. mutabilis change color throughout the course of a single day, driven by a progressive accumulation of anthocyanins in the petals. A flower opens white in the morning, turns blushing pink by midday, and deepens to a rich rose-red by evening. In the straight species, each bloom lasts one day before dropping. In 'Plena', the fully double, peony-form flowers hold longer, and the layered petals make the color shift more gradual and more visible. On a mature plant in October, you will find all three colors simultaneously on the same shrub — white, pink, and red in various stages of the day's progression. This is not a subtle effect.

The shrub itself is fast-growing and substantial. In the Deep South it can reach ten feet or more in a single season, producing large, palmately lobed leaves with a soft, slightly fuzzy texture that gives the plant a lush, almost tropical character. In Zone 7 it dies to the ground in winter and returns vigorously from the roots each spring. In Zone 8 and warmer it is effectively woody and persistent. Either way, it earns its space.