Ardisia japonica 'Hakuokan'

Ardisia japonica 'Hakuokan' is a jewel of the Japanese shade garden, a low evergreen groundcover whose small, glossy, leathery leaves are edged in a clean band of creamy white. The green species, called yabukoji in Japan and marlberry in English, has grown wild in the woodland understory of Japan, Korea, China, and Taiwan for ages, spreading quietly by underground runners into knee-low colonies. 'Hakuokan', a name that reads roughly as white royal crown, is a variegated selection prized by collectors, slower and more compact than the plain species and all the more luminous for the pale margin that catches light in a dim corner.

Plants like this one carry a long cultural history. From the Edo period, Japanese growers cultivated an art of koten engei, the classical horticulture of collecting foliage variants, natural sports, and variegated forms, displayed in special pots and ranked in printed lists modeled on sumo. Yabukoji stood among the traditional subjects of that pursuit, and named variegated forms such as 'Hakuokan' descend from exactly that connoisseur's eye for the beautiful mutation. The bright red berries that follow the flowers have long earned the plant a place in Japanese New Year arrangements as a token of good fortune.

In midsummer, small star-shaped flowers of white blushed with pink nod in little clusters beneath the leaves, followed in autumn by round, coral-red berries that hold through winter against the evergreen foliage, one of the plant's quiet pleasures. The genus name Ardisia comes from the Greek ardis, a spear point, for the sharp tip of the flower's anthers, and japonica marks the plant long associated with Japanese gardens. Low, slow, and evergreen, 'Hakuokan' asks little and gives a long season of interest.

Beyond the garden, the green species holds a serious place in Chinese herbal tradition, where the whole herb, known as zi jin niu, was gathered and decocted chiefly for coughs and complaints of the lungs, a use modern laboratories have traced to a well-studied compound called bergenin. In cultivation, set 'Hakuokan' in part to full shade, in moist, humus-rich, acidic soil, as a refined groundcover for woodland beds, shaded borders, and Japanese-style plantings, where the white margins lift the gloom. Pair the plant with ferns, hostas, and hellebores, shelter the foliage from hot afternoon sun, and let the slow colony knit itself together over time.