Add a Touch of the Far East to Your Garden: Pieris japonica
(Editor's Note: This article was originally published on May 9, 2010. Your comments are welcome, but pleae be aware that authors of previously published articles may not be able to respond to your questions.)
Pieris is of the Ericaceae or Heath family, is native to the Far East, and has only seven species, most of which are suitable only for temperate growing zones. Pieris is related to rhododendron and azalea and, as such, is a broad-leaved evergreen. Each of the individuals has the distinction of brilliant crimson or bronze new growth, the leaves shiny and looking almost like flowers themselves. The plant is slow growing and needs little pruning, other than removing spent flower blossoms.
These lovely shrubs require some care in harsh climates; they do not fare well in extreme cold, high wind, hot dry conditions, or drought. The shrub requires some shade, particularly in the afternoon, and wherever the salt content of the water is high, the plants must be leached frequently. Chlorosis is usually caused by alkaline or neutral-pH soils. Lace bugs suck the juice from the leaves, giving the same yellow appearance of chlorosis. In crowded conditions, Pieris is susceptible to some fungal diseases. Literature states the all parts of the plant are toxic if ingested.
Pieris makes a splendid statement in an open entryway, or in a Japanese or Oriental garden setting, especially when the flower buds begin to open from February through April (depending on the region).
The most common species found in nurseries is Pieris japonica (Adromeda japonica) or lily-of-the-valley shrub, with its large, drooping clusters of creamy white urn-shaped flowers. It has an upright dense growth habit to 10 feet. In cool climates, it takes full sun, but must have part shade elsewhere. P. japonica grows in zones 5 to 8.
Several cultivars of Pieris japonica are available in different regions. P. japonica ‘Dorothy Wycoff’ has dark red buds which open into light pink flowers. This lovely variety is suitable for zone 5 and warmer, though can survive in zone 4 with protection.
P. japonica ‘Mountain Fire’ has brilliant red new growth, but is stated to only be suitable for zones 7 to 8.
P. japonica ‘Purity’ is a compact plant with large pure white flowers. Suitable for zones 6 to 8.
P. japonica ‘Variegata’ has green leaves with white margins after maturing. Suitable for zones 6 to 9.
P. japonica ‘Pygmaea’ or P. japonica ‘Compacta’ are new dwarf cultivars that never grow taller than 12 inches.
Other members of the Pieris genus
Other species of Pieris might be more difficult to find, but definitely worth the effort.
P. floribunda (Adromeda floribunda) is also called Mountain Pieris. This shrub is quite hardy to cold temperatures and is more tolerant of hotter, dryer air than others. P. floribunda is rounded, compact, and hardy in zones 5 through 9.
P. formosa is also called Himalayan Pieris. This rangy shrub grows from 10 to 16 feet, with dark green leaves up to 6 inches long. The new growth is bronze to scarlet, and the flowers bloom in April. Less hardy and more suitable for zones 7 to 9.
P. formosa forrestii is also known as Chinese Pieris. This shrub has a more dense growth habit, with spreading and drooping flower clusters, and bright scarlet new growth. This species needs more shade than others, as well as moist, organic soil. The shrub is hardy to zone 8
For the gardener looking for an elegant, graceful shrub to fill those shady spots in the landscape, Pieris japonica and its relatives can’t be beat.