American Nurseryman Magazine - Horticulture Magazine and Horticulture Books - Hibiscus syriacus - August, 2014 - DEPARTMENTS

American Nurseryman Magazine - Horticulture Magazine and Horticulture Books - August, 2014

DEPARTMENTS

Field Notes: Hibiscus syriacus

Thinking back to childhood, one of the very first plants I remember is rose of Sharon. I knew them to be the large shrubs that lined the back yard and formed the border between our property and the neighbor's; I also knew them to be a bit confusing. I never understood who Sharon was, nor why we had her roses-and no one ever bothered to enlighten me. Being the youngest in the family has many advantages; being encouraged to live with misperceptions is not chief among them.



Photos courtesy of Sally Benson

Despite my annoying questions, however, Hibiscus syriacus-rose of Sharon-was one of my mother's favorite plants. She had a fondness for tropicals, and often populated the deck with Hibiscus rosa-sinensis, rose of Sharon's warm-climate cousin. My father loved hollyhocks (Alcea rosea), also a member of Malvaceae; these were planted at the back of his vegetable garden. So rose of Sharon became that happy medium, but one that proved its worth throughout the years, long after the tropical and perennial blooms were replaced.

Name: Hibiscus syriacus

Common Name: rose of Sharon, shrub althea

Hardiness: Zones 5 to 8

Mature height: 8 to 12 feet

Mature spread: 4 to 8 feet

Classification: Multistemmed, deciduous shrub

Landscape use: Specimen, espalier or informal hedge; quickly forms a shrub border

Ornamental characteristics: Showy, tropical-looking, five-petaled flowers, usually with a deeper eye and dramatic staminal column; species produces pink to lavender, sometimes white blooms, while cultivars show reliable pink, white and blue shades; clean, toothed and lobed, medium-green foliage along long stems

Hibiscus syriacus is a vigorous, vase-shaped, multistemmed shrub reaching to about 8 to 12 feet tall. It's sometimes trained as a small tree or espalier, where it works well as a specimen, but rose of Sharon often is used as a flowering hedge. This was how I came to know the plant, crawling under the foliage to the neighbor's yard to retrieve a wildly errant croquet ball or peering through the branches to watch the boys play baseball.

This natural fence blooms each summer with hundreds of pink or white, five-petaled flowers that resemble hollyhocks; although the hollyhocks are long gone, the hedge is still standing. Before they blossom, large, ovoid, pregnant buds form clusters at the tips of long, graceful branches. The showy, 3- to 4-inch flowers never disappoint. They appear painted at the center, from which emerges a dramatic, center staminal column-fuzzy and unusual, it captured my young imagination as it attracted both bees and butterflies.

Distinctive and deeply lobed, medium-green foliage is coarsely toothed. Although there's very little fall color, the foliage normally remains clean until final leaf drop, often well into the season. Some rust and blight have been reported, but my plants, located in full sun, have battled only the occasional Japanese beetle.

My parents' property hosted rich, black, Midwestern farm soil, but rose of Sharon is tolerant of less hospitable environments, including clay. My mother considered it a passalong plant; whenever friends or relatives established a new home, a small plant was delivered. I have several such plants thriving in wretched soil conditions, as well as several newer, named cultivars that are keeping pace with the straight species. The true blue of Proven Winners' Blue Satin ® is a particular favorite, as is the company's pure White ChiffonT. Both established quickly and continue to be real performers. While the species has aggressive tendencies, the cultivars have been well-behaved.

Sally Benson, Editorial Director
American Nurseryman
sbenson@mooserivermedia.com