Althea, Hibiscus syriacus, is a pretty late flowering shrub. This plant can be found in the Butterfly Garden at the Wilson Ag. Center located at 1806 S. Goldsboro Street.

Althea grows 8 to 12 feet high and 6 to 10 feet wide. It grows as a shrub or small tree with very erect branches.

It transplants well and grows in about any soil except those extremely wet or dry. Does best in moist, well-drained soils supplemented with organic matter. Althea grows in a wide range of pH levels. It flowers best in full sun but will do ok in partial shape. Prefers hot weather so does well in southern gardens.

Prune althea heavily in early spring. This will encourage larger flowers.

The leaves of althea are medium to dark green in the summer. They hold their color late and have a poor yellow fall color. Sometimes althea tends to leaf out late in the spring so do not worry if this happens to you.

Althea flowers in July, August through September. Flowers can be white, red, purple, violet or a combination. Flowers can be single or double. Flowers are typically 2-4 inches across.

Many cultivars are available. Some favorites are 'Diana' which has large pure white flowers that remain open at night. It flowers over a long period of time with relatively few fruits. The leaves are a dark waxy green. 'Helene' has essentially white flowers with a reddish purple blush at the base. It blooms heavily in August. It does not set much fruit.

Hibiscus plants are like daylilies in each flower only lasts one day. If flowers are not deadheaded a 5-valved fruit capsule will persist through the winter. Seeds require no pre-treatment for propagation and therefore can self-sow which may be a nuisance in the landscape. We have not seen any self-sowing Althea in our garden.

Althea can be the host of several diseases and insects although the plants at the Ag. Center has never exhibited any of these pest problems. Leaf and bacterial spot, blight, canker, rust aphids, Japanese beetles, scale, foliar nematodes and whitefly.

Althea is a valuable plant to add to the southern landscape for late season flowers. Plant in groups, masses or shrub borders. The plants growth habit doe not make for a very attractive single specimen. Can be used for as screen or hedge.

The Wilson Display Garden, at 1806 S. Goldsboro Street and is open from dawn until dusk. Come visit the garden! Gardening questions can be answered, Mondays and Fridays from 1 until 3 PM by calling 237-0113.

Date Created: 7/11/03.