Althea or Mallow tree (Hibiscus syriacus)

With its magnificent brightly colored flowers, the Hibiscus has the enchanting accents of the tropics. There is, however, a shrubby form, which thrives in our more northern latitudes and delights our summers with its multicolored flowers: Hibiscus syriacus, or althea. A bit of dream in our garden or on the balcony. Althea, hibiscus, tree mallow...Originally from India and China, from where it was introduced to Europe around 1580, Hibiscus syriacus comes in many popular names: althea, tree mallow, tree mallow tree, garden hibiscus (not to be confused with marsh hibiscus), etc. It is a very easy-going shrub, endowed with great adaptability.

The very spectacular flowering is constantly renewed from July to October. The flowers, superb and ephemeral corollas of 6 to 8 cm in diameter, appear successively, solitary or worn in pairs. Blue, pink, white or red, single or double, they sometimes have a stronger heart, which highlights their decorative effect.

Althea, a shrub with multiple uses

Grown in a free form, your Hibiscus syriacus will form beautiful shrubs, very branched bushes with erect stems. They can reach 2 to 3 m in height and around 1.50 m in width.

Along with other shrubs or perennial plants, they will bring a touch of cheerfulness to your flowerbeds (planting distances: approximately 1.50 m). You can also plant Hibiscus syriacus in perennial beds, to give a little dimension to the decor. One or more hibiscus planted in mixed hedges will look great (read also: Flowering hedge: shrubs for every season). In small gardens, they are also suitable isolated on a lawn (read: A flowering lawn). If you are patient, you can prune a hibiscus into the shape of a small tree. Thanks to successive pruning, build a short trunk while preserving the volume of the head. You will thus have a beautiful miniature tree, original and flowering.

Since hibiscus flowers on current year shoots, you can prune it every year, in February-March. All lateral shoots are cut back between 8 and 10 cm from their starting point, to prevent the plant from forming too much wood and becoming bare. The antler can also be reduced by a third of its height.

Due to its fairly compact appearance and its good adaptation to severe pruning, the hibiscus is well suited to a balcony. Don't resist the original elegance of the hibiscus on a stem. You can buy it already formed. Install it in a container 30 to 40 cm deep. A square bin is very suitable. Your very flowering mini tree will not fail to get noticed! For planting, prefer a location in full sun, sheltered from prevailing winds, in good, balanced, fertile and properly drained garden soil. Once planted, hibiscus poses few problems. Just be careful that the plant is not exposed to late spring frosts or cold winds, which can cause the forming flower buds to wilt and drop off. Hibiscus tolerates limescale well.

Interview

Hardy, the Hibiscus syriacus resists up to -15°C without problem and under the snow it will certainly resume the following spring from the base or higher depending on the snow cover present before the cold weather. No specific maintenance is recommended, other than good fertilization in spring, to stimulate growth and copious watering on heatwave evenings. As for enemies and diseases, beware of aphid attacks in May-June. No illness is really to be feared.