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Olearia phlogopappa

asthma bush

Asteraceae Southeastern Australia

Attracts Pollinators Attracts Butterflies Drought Tolerant Fragrant (light)Container Friendly

SunFull Sun – Part Shade

WaterLow · drought-tolerant

HardinessZones 8–10

Overview

Olearia phlogopappa is an evergreen shrub reaching 3-8 feet (0.9-2.5 m) tall and 3-6 feet (0.9-1.8 m) wide, with an upright, much-branched habit and slender, greyish stems. Leaves are narrow to oblong, 0.4-1.6 inches (1-4 cm) long, grey-green above and densely white-hairy beneath, with toothed margins and an aromatic scent when crushed. Daisy flowers about 0.6-0.8 inch (1.5-2 cm) across cover the bush in spring, each with white, mauve, or pale blue ray florets around a yellow centre. The flowers are followed by small dry seeds with a tuft of bristles. Growth is fast, and plants are short-lived, often persisting 5-10 years. It grows in well-drained soils in sun to part shade and tolerates wind and frost but declines in waterlogged ground. Older plants become open and woody at the base.

Native Range

Native to southeastern Australia, in Victoria, New South Wales, Tasmania, and South Australia. Grows in eucalypt forest, woodland, subalpine scrub, and along watercourses on a range of well-drained soils, from near sea level to about 5,000 feet (1,500 m).

Suggested Uses

Used as an informal screen, windbreak filler, and spring-flowering shrub in native and cottage-style gardens, spaced 3-5 feet (0.9-1.5 m) apart. Suited to exposed and frost-prone sites where many shrubs struggle. Grows in containers of at least 5 gallons (19 L) with free-draining mix.

How to Identify

Recognized by narrow, toothed grey-green leaves 0.4-1.6 inches (1-4 cm) long that are densely white-hairy beneath and aromatic when crushed. The bush is covered in spring with daisy flowers 0.6-0.8 inch (1.5-2 cm) across in white, mauve, or pale blue. The combination of dusty white leaf undersides and massed daisy flowers separates it from other Olearia spp. species.

Appearance

Size & Dimensions

Height3' - 8'

Width/Spread3' - 6'

Reaches mature size in approximately 3 years

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~6 weeks

Spring

Flowers in spring, mainly September to November in its native range. The daisy flowers open over a period of 4-6 weeks and can briefly cover the foliage. Flowering is heaviest in open, sunny positions.

Detailed Descriptions

Flower Description

white, mauve, or pale blue

Foliage Description

grey-green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 5-9 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.0(Neutral)

357912

Soil Types

sand loam clay

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

2-3 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Grows in full sun to part shade in well-drained soil of low to moderate fertility. Water during establishment; established plants tolerate dry periods, wind, and frost. It declines in heavy, waterlogged ground, where root rots develop. Light tip-pruning keeps the bush dense, as older plants become open and woody at the base. Plants are short-lived, often replaced after 5-10 years. Few serious pests affect it.

Pruning

Trim lightly after flowering and tip-prune through the growing season to keep a compact, leafy shape. Cutting back into bare old wood reshoots poorly, so trimming is kept to leafy stems. Hard renovation is unreliable, and worn plants are usually replaced.

Pruning Schedule

spring