Plants
Hibiscus
Hibiscus syriacus · Malvaceae
Garden hibiscus is the late-summer gap-filler in the border: just when most shrubs have finished, it really gets going from July into September. Each funnel-shaped flower lasts only a day, but it is replaced morning after morning by hundreds of fresh buds. When we select stock at the Veiling Rhein-Maas auction we look for well-rooted, nicely branched plants so the shrub stands firm in the garden from the start.
- Light
- Full sun and warmth; large-flowered or double varieties appreciate a wind-sheltered spot out of harsh midday heat.
- Watering
- Keep evenly moist but never wet; water thoroughly during dry spells and flowering, and avoid waterlogging.
- Care level
- Easy
- Botanical
- Hibiscus syriacus
Botanically, garden hibiscus (Hibiscus syriacus), also called rose of Sharon or shrub althea, is a deciduous shrub in the mallow family (Malvaceae). Over the years it reaches up to three metres, growing upright and loosely branched. It should not be confused with the frost-tender indoor hibiscus (Hibiscus rosa-sinensis), which is not winter hardy.
The range of varieties runs from pure white to deep violet-blue blooms, often with a contrasting dark eye at the centre. Single, semi-double and fully double forms exist. Popular cultivars include Blue Bird (Oiseau Bleu) in luminous violet-blue, Woodbridge in strong pink-magenta, Diana in clean white, and the compact, near-sterile Chiffon series that flowers especially freely.
In floristry and garden design hibiscus shines as a specimen, in an informal hedge or in a large container on the terrace or balcony. Because it leafs out late in spring it stays bare for a while, then performs all the more generously. The individual blooms make poor cut flowers, but the shrub is a reliable, long-flowering anchor for the summer border.
Stylistically, garden hibiscus pairs well with other late-summer structural plants: lavender and catmint at its feet, grasses for movement, plus hydrangeas or butterfly bush as companions in the same flowering window. The result is a border that carries from high summer into autumn.
Care
- 01Choose a full-sun, warm position; in hot midday spots, large-flowered and double varieties do better in a sheltered, wind-protected place.
- 02Keep the soil loose, humus-rich and free-draining, neutral to slightly alkaline; avoid waterlogging at all costs.
- 03Water evenly during dry spells and while in bloom, especially for newly planted specimens and those in containers.
- 04Prune in early spring: hibiscus flowers on the current year's wood, so a firm cut encourages large blooms without sacrificing buds.
- 05For the first two to three seasons protect the root zone in winter with leaves, brushwood or straw; established shrubs tolerate frost down to roughly minus 17 degrees.
- 06Be patient with leaf-out: hibiscus breaks bud late and stays bare well into spring, which is normal and no cause for concern.
Frequently asked
- Is garden hibiscus toxic to cats, dogs or children?
- No. Garden hibiscus (Hibiscus syriacus) is considered non-toxic to people and pets such as cats, dogs and rabbits. It can therefore be planted without worry in a household with children or animals.
- Why does each hibiscus flower last only one day?
- It is simply the plant's nature: each funnel-shaped bloom opens in the morning and fades by evening. But because the shrub keeps pushing out fresh buds, it flowers almost continuously from July into September. Spent flowers can be left in place, they drop on their own.
- When and how should I prune garden hibiscus?
- Best in early spring, before the late leaf-out begins. Since hibiscus flowers on fresh, current-year wood, even a hard cut does not cost you blooms; instead it keeps growth compact and produces larger flowers.
- Is garden hibiscus suitable for a container on a balcony or terrace?
- Yes, in a sufficiently large pot with good drainage it thrives in a container too. The keys are a sunny, sheltered spot, regular watering, and winter protection for the root ball, since container plants are more cold-sensitive than shrubs in the ground.