Althea, a fantastic hibiscus

Pink double althea flower with crimson red center.

Althea, also called Hibiscus or Rose of Sharon, is a very decorative shrub.

A list of Althea facts

NameHibiscus syriacus
Family – Malvaceae (mallow family)
Type – shrub

Height – 3 to 13 feet (1 to 4 m)
Exposure – full sun, part sun
Foliage – deciduous
Flowering – July to November

Caring for this plant, from planting to blooming and including watering and pruning, is easy and this will give your althea magnificent flowers.

Planting althea

Planting althea in pots

All year round, the shrub must be planted in a soil mix designed for flowering plants, for planting, or any universal soil mix.

  • Repot in the spring, at least every second year, in a pot that is slightly larger than the previous.

Planting althea in the open

Prefer planting in fall or spring if you have purchased the shrub in a pot or a container.

  • Choose a sun-bathed area, sheltered from stronger winds.
  • Follow our advice on planting shrubs.

Propagating althea

Cuttings are very easy to perform in spring for althea.

Simply keep cut stems in a vase with water, and plant as soon as a few roots appear.

Pruning althea

At the beginning of spring, towards February-March, it is time to prune your althea.

Althea will bloom on new growth, so you can prune every year.

However, try to avoid pruning late in the season, since this would tend to reduce blooming.

  • Remove all branches that grow inwards so that the shrub can filter light through the inside.
  • After that, cut remaining stems back by about ⅔, just above an outward-facing bud.

All there is to know about althea

Althea grows into nice hardy shrubs.Althea, also part of the Mallow familly, is very certainly one of the most beautiful flowering shrubs. Not only is it well suited to any garden, but it also does great on terraces and balconies.

Even if this shrub prefers warm climates, several varieties are perfectly adapted to our harsher climates, like Hibiscus rosa sinensis or Hibiscus syriacus.

The numerous cultivars that are circulating allow for as many shapes and colors, and each is more beautiful than the next.

Whatever the configuration – hedge, flower bed or stand-alone – althea will enchant you with the beauty of their flowers.

Its blooming is very generous, in that it is both opulent and constantly renews itself from July to October and even November if the weather stays mild.

Smart tip about althea

If it freezes in your area, it is highly recommended to winterize your plant with horticultural fleece as early as November!

Credits for images shared to Nature & Garden (all edits by Gaspard Lorthiois):
Double althea by Leonie Schoppema under Pixabay license
Althea stalk by tunechick83 under Pixabay license