Zieria spp.

Attracts Pollinators Attracts Butterflies Deer Resistant Drought Tolerant Fragrant (moderate)Container Friendly

SunFull Sun – Part Shade

HardinessZones 9–10

Overview

Zieria spp. is a genus of about 60 aromatic evergreen shrubs in the citrus family, almost all native to Australia, with a single species in New Caledonia. Most are small to medium shrubs, ranging from under 1 ft (0.3 m) to about 10 ft (3 m) tall, with opposite leaves divided into three leaflets that release a strong scent when crushed; the aroma varies by species from citrus-like to pungent. Clusters of small star-shaped flowers, each with four petals, open from late winter into spring in shades of white to pink. Zieria spp. closely resembles the related Boronia spp. but has four stamens rather than eight, a reliable point of separation. Foliage and stems are often dotted with oil glands typical of the family. Many species have very restricted ranges and a number are listed as rare or threatened in the wild. Most are frost-tender and require sharp drainage, and some are short-lived in cultivation, which keeps the genus mainly in the hands of native-plant growers rather than in general garden use.

Native Range

Zieria spp. is native chiefly to Australia, where it occurs in every mainland state and is most diverse in eastern New South Wales and Queensland; one species reaches New Caledonia. The shrubs grow in heath, dry sclerophyll forest, and rocky outcrops, often on shallow, nutrient-poor soils.

Suggested Uses

Zieria spp. is grown in Australian native gardens, low-water and coastal plantings, and rockeries in frost-free regions. The aromatic foliage and spring flowers suit informal shrub borders and containers. Frost sensitivity, drainage needs, and the short life of some species limit it to specialist and regional plantings.

How to Identify

Identify Zieria spp. by opposite, three-parted leaves that are aromatic when bruised and often warty with oil glands, borne on shrubby, sometimes hairy stems. The small flowers have four petals and four stamens, arranged in branched clusters from the leaf axils. The four-stamen count separates Zieria spp. from Boronia spp., which has eight, while the trifoliate leaves set it apart from many other heath shrubs.

Appearance

Size & Dimensions

Height1' - 10'

Width/Spread1' - 6'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~5 weeks

Winter Spring

Flowering runs mainly from late winter into spring, broadly August to November in the southern hemisphere. Branched clusters of small four-petalled flowers cover the shrubs and draw native bees and other insects. Dry, segmented capsules follow and split to eject the seeds.

Detailed Descriptions

Flower Description

White to pink

Foliage Description

Green, aromatic

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 rocky

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Time to Maturity

3-5 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Zieria spp. needs full sun to light shade and sharply drained sandy, loamy, or rocky soil with a pH around 5.5 to 7.0. As a member of the citrus family from lean habitats, it grows on low-phosphorus soils and is sensitive to standard fertilizers. Established plants tolerate dry spells, but most are frost-tender and suit only mild, warm-temperate to subtropical climates. Good air movement and free drainage reduce the root-rot and fungal problems to which the genus is prone. Light, regular tip pruning keeps plants bushy, since some species grow open and woody with age.

Pruning

Light tip pruning after flowering keeps Zieria spp. compact and slows the tendency to become open and woody. Hard cutting into bare old wood is avoided, since regrowth from leafless stems is unreliable. Spent flower clusters are trimmed along with the tips.