PL. —Grevillea rosmarinifoliaBotanical illustration — drop image
Grevillea rosmarinifolia

Rosemary Grevillea

WinterSpringSummerFall
8a10bHardiness zone
Background

Grevillea rosmarinifolia is an evergreen shrub native to southeastern Australia, grown in warm-climate gardens for its needle-like foliage and loose clusters of curved pink to crimson flowers that reliably attract hummingbirds. It fits naturally into Mediterranean, drought-tolerant, and California-inspired plantings.

Once established, it is highly drought tolerant and demands sharp drainage above all else. Phosphorus sensitivity is the defining nutritional concern for all Proteaceae — standard or high-phosphorus fertilizers can damage or kill the plant; use a dedicated low-phosphorus formula or none at all. A soil pH of 5.5–6.5 suits it best. Prune lightly after the main late-winter-to-spring flowering, cutting only into live green growth; old leafless wood rarely regenerates. In zone 8a, plants may sustain top-kill below 15°F but often regrow from the crown.

The dense, prickly stems provide nesting cover for small birds, and the nectar-rich flowers support pollinators in late winter when few other shrubs are in bloom.

Care guide
SunFull sun to part shade
WaterLow
SoilWell-drained, sandy or loamy, slightly acidic
Spacing4–6 ft
Height3–8 ft
Zone8a – 10b
Frost hardy
Seasonal tasks
winter
watchCover plants with fleece if temperatures below 15°F are forecast; established plants often recover from the crown even if top-killed.
spring
cutPrune lightly after the main late-winter-to-spring flowering flush, cutting only into green growth to maintain a compact habit.
sowPlant in spring in well-drained, low-phosphorus soil; avoid bone meal or any high-phosphorus amendment.
summer
watchMonitor for rapid wilting or yellowing of foliage — early signs of Phytophthora root rot in slow-draining soil.
cutRemove dead or crossing stems in late summer; restrict cuts to outer live growth only.
fall
watchCheck for fungal leaf spotting in humid or wet conditions; thin interior stems to improve air circulation.
Common problems

Phytophthora Root Rot

Symptoms

Wilting despite moist soil, yellowing leaves, stunted growth, and dark, decayed roots and crown tissue. Vines may collapse during hot weather.

Treatment

Plant in well-draining soil and avoid waterlogging. Remove and destroy affected vines. Improve drainage with raised beds or amended soil and avoid overwatering.

Fungal leaf spot

Symptoms

Brown or purplish spots on the leaves, often ringed with a yellow halo, that spread and merge in warm, humid, or wet weather; heavily spotted leaves yellow and drop early.

Treatment

Pick off spotted leaves and clear fallen debris to remove overwintering spores. Improve air circulation by thinning, and water at the base so foliage dries quickly. If it persists, apply a copper- or sulfur-based fungicide at the first sign.