tree

Sea Hibiscus

The Story

Plant Bio

Hibiscus tiliaceus, the sea hibiscus, is a dense, spreading evergreen tree native to Australia's tropical and subtropical coastlines, where it forms a broad, rounded canopy of large, heart-shaped leaves. The foliage features dark green upper surfaces contrasted by pale, felted undersides, providing a distinct two-toned appearance in coastal breezes.

The species produces solitary, bright yellow flowers with deep crimson throats that open in spring and summer, darkening to orange or apricot before they drop. It is highly adapted to maritime environments, demonstrating exceptional tolerance to salt spray, saline soils, and occasional tidal inundation.

Uses & Benefits:

Provides a dense, tropical-looking canopy with large heart-shaped leaves and colour-changing yellow flowers.

Serves as a highly effective windbreak and soil stabiliser in exposed, salt-prone coastal environments.

Supports native nectar-eating birds, acts as a host plant for butterflies, and provides shelter for coastal frogs.

Essentials

At a Glance

Plant Type

Tree

Height

393 inches

Width

236 inches

Light

Full Sun, Partial Sun

Zones

9, 10

Water

Moderate

Humidity

High

Lifespan

Long-lived

Native To

Australia

Toxicity

Non-toxic (hairs may cause minor skin irritation)

Bloom period

Spring – Summer

In flower about 4 months of the year

Planting

How to Grow

Select a planting site in full sun to partial shade with adequate space for a spreading canopy.
Dig a hole twice the width of the root ball and backfill with native soil, ensuring the plant sits at its original pot depth.
Water thoroughly after planting to settle the soil around the roots and eliminate air pockets.
Apply a thick layer of organic mulch around the base, keeping it clear of the main trunk to prevent rot.

Pro Tip

Prune lightly after flowering to maintain shape, but avoid cutting back into old, leafless wood as it fails to shoot back reliably.

Keep It Thriving

Care Guide

Do

Water regularly during the first growing season to establish a deep root system.
Protect young plants from frost using temporary covers or physical barriers.
Prune lightly after the summer flowering flush to control size and density.

Don't

Do not prune hard into old, bare wood as regrowth will be patchy or non-existent.
Do not over-fertilise, which leads to excessive, weak foliage growth at the expense of flowers.
Do not plant in heavy inland frost zones without adequate overhead canopy protection.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Pest Check
Propagate
Prune

Watch Out For

Pests & Diseases

Common Pests

In the Garden

Landscape Uses & Companions

Landscape Uses

Coastal WindbreakPrivacy ScreenShade TreeErosion Control

Companion Plants

Crinum pedunculatum Casuarina equisetifolia Scaevola taccada

Multiply

Propagation Methods

Good to Know

Common Questions

Sea Hibiscus questions

What zones can Sea Hibiscus grow in?

Sea Hibiscus is hardy in USDA Zones 9–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

When does Sea Hibiscus bloom?

Sea Hibiscus typically blooms in spring through summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Sea Hibiscus need full sun?

Sea Hibiscus does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Sea Hibiscus drought tolerant?

Yes — once established (usually after the first full season), Sea Hibiscus handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.