Rose of Sharon.

At a glance

Care level

Easy

Plant type

Deciduous shrub

Light

Full sun to partial shade

Indoor light

Bright indirect

Water

Every 5 to 10 days

Mature size

3 to 4 meters

Growth rate

Medium

Hardiness

USDA 5 to 9

Bloom time

Mid summer to early autumn

Care

Plant in a spot that gets plenty of sun to encourage the best blooms. Keep an eye out for aphids or whiteflies during the growing season. Prune in late winter to maintain shape and encourage new growth for the coming year.

Watering

Water deeply once a week, increasing frequency during hot, dry spells.

Feeding

Apply a balanced fertilizer in early spring as new growth begins.

Pruning

Prune in late winter while the plant is dormant to shape and remove dead wood.

Repotting

Repot only if the plant becomes root bound in its container.

Soil

Well draining, fertile soil

Soil pH

6.0 to 7.5

Temperature

-25 to 35°C

Humidity

40 to 70%

Drought tolerance

Moderate

Lifespan

Perennial, typically 20 to 50 years.

Deer and rabbits

Moderate

Safety

People

The plant is generally considered non toxic to humans, but ingestion of large amounts may cause mild stomach upset.

Pets

The Rose of Sharon is considered toxic to cats and dogs if ingested.

Children

The seed pods can be a choking hazard if swallowed by small children.

Contact allergens

The foliage can cause mild skin irritation in sensitive individuals.

Airborne allergens

The pollen is not typically a major cause of hay fever.

Edibility

While the flowers are sometimes used in teas, they are not a primary food source and should be consumed with caution.

How to identify it

• Vase shaped deciduous shrub
• Three lobed serrated leaves
• Large trumpet shaped flowers
• Prominent central stamen column

Height

2 to 4m

Spread

1.5 to 3m

Leaves

green, yellow, deciduous

Flowers

purple, pink, white, blue, 5 to 10cm

Fruit

brown, Autumn

Problems to watch for

• AphidsCommon
• Japanese BeetlesCommon
• Leaf SpotCommon
• ChlorosisUncommon
• Scale InsectsUncommon
• Sooty MoldUncommon

Growing it

Propagation

cuttings, seed

When to plant

spring, autumn

Overwintering

Apply a layer of mulch around the base to protect roots from extreme temperature fluctuations. Prune back dead wood in late winter.

In containers

It grows well in large containers, provided they are at least 40 liters in volume.

Pair with drought tolerant perennials to maintain a low maintenance border.

Grows well with

• Lavender — They share similar sun and soil requirements.
• Coneflower — These perennials provide a nice color contrast in late summer.

Similar species

• Rose of Sharon — This is the same species, often sold under different common names.

Science

Family

Malvaceae

Genus

Hibiscus

Order

Malvales

Class

Magnoliopsida

Native range

Temperate regions of East Asia.

Conservation

This species is not of conservation concern and is widely naturalized in many regions.

It thrives in sunny, well drained sites and often self seeds in favorable conditions.

Value to wildlife

nectar source

Pollinators

bees, butterflies, hummingbirds

Uses

ornamental shrub, hedging, pollinator garden

Taxonomy resolved against GBIF.

Questions people ask

Why is my hibiscus not blooming?

It likely needs more direct sunlight to produce flowers.

Should I prune it?

Yes, prune in late winter or early spring to encourage more blooms.

Where the name comes from

The name Hibiscus comes from the Greek word for mallow, while syriacus suggests it originated in Syria, though it is actually native to Asia.

Good to know

• It is the national flower of South Korea.
• The flowers typically last only for a single day.
• It is remarkably tolerant of urban pollution.

Also in

• Plants toxic to cats and dogs