Rose of Sharon is a mainly deciduous shrub hardy as far north as USDA zone 5. It grows best in rich, loamy soil to heights and widths up to 15 feet, but many varieties are smaller. Flowering occurs on new growth beginning in June or July and can continue until frost. Rose of Sharon is also known as Hardy Hibiscus or Shrub Althea.
Released by the United States National Arboretum, Aphrodite is a smaller shrub growing to 8 feet. The large, 4- to 5-inch diameter flowers begin in late June or early July, covering the shrub with blooms shaded in a delicate pink and deep red centers. The red "eye" both complements and contrasts with the pink outer petals. Aphrodite has multiple stems and branches out from the ground up.
Pure white blooms from mid-summer through autumn grace the branches and waxy green foliage of Diana. Diana is a triploid, meaning it has three complete sets of chromosomes. Like others released by the United States National Arboretum, Diana seeds itself less freely. Typical growth is up to 10 feet tall and 8 feet wide.
Featuring eye-catching blooms of lavender pink with red centers, these flowers are a full 5 inches across. Minerva is another United States National Arboretum variety. The shrub reaches a full 10 feet tall and 10 feet wide.
Developed in the Netherlands by Rien Verweij, Blue Satin is considered a stronger replacement for Blue Bird. Mid-summer brings large single flowers in rich blue with a small purple eye. This variety grows eight to 12 feet tall and up to 4 feet wide.
Two varieties developed in England called Lavender Chiffon and White Chiffon have won gold and silver medals from the Royal Horticulture Society in the Netherlands. Chiffon has the classic five petal shape with a powder puff of petal-like stamens at the center, a feature unique to the two varieties.
An accidental find among a shipment of seedlings, Freedom is a double flowered variety with dusky red-pink blooms. The tightly packed petals still show characteristics of single blooms. Freedom will be more widely available in the future as its popularity grows.
Possibly the only miniature Rose of Sharon plant, Lil' Kim grows only 3 to 4 feet tall. The single flowers are pure white with a deep red eye. The red portion of each petal appears to bleed into the white at the edges, creating a spiked appearance.
The large, clear pink double flowers are not the only feature of this shrub. Sugar Tip sports bright, variegated foliage. The bluish green leaves have cream-colored margins, which make this cultivar somewhat unique. Unlike many in its family, Sugar Tip does not produce seeds, which makes it an ideal low-maintenance Rose of Sharon.