One-Sided Bottlebrush

One-Sided Bottlebrush (Calothamnus quadrifidus) is a Western Australian native that shrugs off the conditions that finish other shrubs: salt wind, poor sand, long dry spells and frost. It grows to about 2.5m tall and 2m wide, with fine pine like foliage and red flower brushes that form along one side of the stem, hence the name. Honeyeaters find it within weeks of the first flowers.

Why you'll love it

• It handles a genuinely hard site. Drought tolerant, frost hardy, wind tolerant, salt tolerant and content in poor soil. Very few shrubs tick all five.
• Honeyeaters love it. The nectar rich brushes pull small native birds in.
• Texture that reads all year. The needle fine grey green foliage looks good out of flower.
• An informal screen at a useful height. At 2.5m it blocks a fence line without turning into a tree.
• Almost no upkeep. No feeding schedule, no spraying, one light trim after flowering.

Where it works best

Screening and privacy. Plant 1.5m apart for an informal screen. At that spacing the plants merge into a continuous 2.5m barrier over three or four seasons.

Windbreaks and coastal gardens. This is where it earns its place. A staggered double row at 1.5m centres filters wind rather than blocking it, which is what an exposed block needs, and salt spray does not mark the foliage.

Feature and mass planting. A single plant shows off the one sided brushes beside a path, and drifts at 1.5m spacing suit a poor bank.

Growing one-sided bottlebrush in Australia

Position and climate. Full sun, always. Shade makes it thin and cuts the flowering right back. It suits warm temperate, cool temperate, Mediterranean and arid gardens and is frost hardy once established. Humid tropical and subtropical summers are its weak point, where the fine foliage gets fungal problems.

Soil. Sandy, gravelly and poor soils are exactly right, since this is a plant of the Western Australian sand plains. On clay, mound the planting position up by 200mm to 300mm. Avoid rich composted beds.

Water and feed. Water weekly for the first summer to get the roots down, then leave it alone. Use a low phosphorus native fertiliser once a year at most, since like many Western Australian natives it resents phosphorus.

Pruning. Tip prune from a young age to build density, then trim by up to a third after flowering. Regular light pruning beats occasional hard cuts, and old woody plants do not always reshoot from bare stems.

What to expect when it arrives

This species is grown here in four sizes: tube stock, 140mm pots in packs of ten, 200mm in packs of six, and 250mm in packs of three. Tube stock is the value choice for a long screen or windbreak. The 200mm and 250mm plants arrive branched and give a visible plant straight away.

The wiry foliage travels well and some needle drop in transit is normal. Plants are delivered Australia wide, with delivery from $29.95. Water in thoroughly, keep the moisture up through the first summer, and expect flowering from the second or third year. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• The best bird attracting native plants for Australian gardens
• Browse Australian native shrubs
• Compare plants for windbreaks
• Shop coastal garden plants

Common questions

How far apart should I plant it for a screen?

One and a half metres apart in a single row. For a windbreak, use two staggered rows at the same spacing, which filters wind better than a single dense line.

How is it different from a callistemon bottlebrush?

The flowers form on one side of the stem rather than all the way around, and the foliage is much finer. It is also tougher in dry, sandy and salt exposed conditions than most callistemons.

Will it grow in a humid subtropical garden?

It can, but honestly it is not the right choice. This is a dry climate species, and humid summers bring fungal problems and a shortened life. Look at a callistemon or melaleuca instead.