A complete guide to the Rose of Sharon shrub Althea. It's scientific name is Hibiscus syriacus.
Scroll down for a list of the best Hibiscus Syriacus plant varietes.
They are deciduous shrub plants that can be grown in zones 2-24.
These lovely shrubs originated from eastern Asia.
The 'Rose of Sharon' bush is a substantial garden plant growing to 10-12 feet tall and about 6 feet wide.
So give it plenty of room to grow, as it looks the best when growing to its natural size. I like it as a specimen plant planted alone, and just underplanted with low groundcover perennials or annuals.
When the Hibiscus Syriacus plant is young, it's more upright and compact, but spreads and opens as it ages.
Many rose gardeners like to train it to a single trunk with a tree-like top.
And others like to use the Hibiscus syriacus shrubs as hedges.
This Hibiscus syriacus variety got it's name for the white tips of the leaves, which is very attractive.
The foilage has leaves that are 4 inches long, and they are
often three lobed with serated edges.
Rose of Sharon bushes leaf out later in spring than most other deciduous garden shrubs.
In the fall the foilage drops off, but there are no fall foilage colors.
When they bloom, the bush looks like it's covered with hollyhocks flowers.
The flowers are single, semidouble, or double form, depending on variety.
The blooms are about 3 inches across, many have contrasting red or purple centers.
I tend to like the single blooms better, because they open wider.
However, they also produce unattractive capsule type fruits. So I deadhead spent flowers to prevent the seed capsules from coming.
They are very easy to grow in any garden with plenty of sunshine all day.
They like heat, and actually prefer it, and also tolerate some drought once established.
The following Hibiscus syriacus, although some are hard to find, are some of the best flowering varieties.
ALBA; Single, with pure white flowers about 4 inches wide.
ANEMONIFLORA: Semidouble red flowers with a deep crimson center.
BOULE DE FEU: Double deep violet pink flowers.
COELESH'S: Single blooms that are violet blue with a reddish purple throat.
COLLIE MULLENS: Double purplish lavender blooms.
LAVENDER CHIFFON: The single blooms are lavender with a center of tuft petals.
LUCY: Double with deep rose blooms that have red eyes.
MEEHANII: Small pale purple flowers with dark centers, variegated foilage with creamy white edges. Very pretty.
If you garden where winter temperatures drop to -10 degrees Fahrenheit (-23) Celcius), or lower, it's best to protect young plants by covering them with mulch for the first few years.
Prune back previous season's growth in winter, cutting down to 2 buds. For more pruning tips go the pruning page.
PURPUREA: Semi-double blooms with red eyes.
RED HEART: Single white flowers with red eyes.
WHITE CHIFFON: Single white blooms with centers of tuft petals.
WOODBRIDGE: Single flowers that are deep rose with eyes.
These are sterile triploids and have a very long flower season. Another good thing is that they set very few, or no seedpods. Below are the new varieties.
APHRODITE: Rose pink with deep red eyes.
DIANA: Pure white flowers. My favorite Rose of Sharon.
HELENE: White with deep red eye.
MINERVA: Has ruffled blooms of lavender pink with reddish purple eyes.