Hardiness zones:
Sunset 12-24, cold damage in zone 8-9
USDA 9 (zone 8 with protection) - 11
Landscape Use: Floral accent, background, screen, large informal hedge, small street tree
Form & Character: Evergreen, Mediterranean, semi-tropical, stiff and brittle
Growth Habit: Upright, 8'-15', moderate growth rate ranging from a large shrub to small multiple-trunked tree. With patience and effort, can be trained as a standard (single trunk small tree).
Foliage/texture: Young leaves reddish, pubescent, mature leaves are thick and brittle, lanceolate to 4" long, nearly sessile, aromatic (lemon fragrance), medium coarse texture.
Flowers & fruits: Red bottle brush flowers (stamens tower above with protruding bright yellow or red filaments with sometimes yellow anthers) followed by persistent small round nut-like fruit.
Seasonal color: Yellow or red flowers (red selections seen in America, yellow in Australia) in Spring (some off-season blooms in fall).
Temperature: Tolerant to 20oF.
Light: Full sun
Soil: Well drained soil. Highly prone to leaf yellowing (chlorosis) in Phoenix due to alkaline soil.
Watering: Infrequent deep irrigations especially during summer.
Pruning: Train rigorously when young to attain upright form if desired. Remove crossing branches, else wise prune to raise canopy base. Easily manipulated, but has brittle wood.
Propagation: Seed difficult, cutting easy.
Disease and pests: None that are significant.
Additional comments: Strongly attracts bees when in flower. The species has been responsible for many of the bottlebrush cultivars that are seen in landscapes today, sometimes as hybrids with other Callistemon species. Most of these cultivars have arisen as chance seedlings rather than by deliberate hybridization. Some of the better known marketed cultivars of C. citrinus are 'Mauve Mist' (mauve), 'Burgundy' (purple-red), 'White Anzac'(white), 'Endeavour' (red) and 'Reeves Pink' (pink). Leaf chlorosis makes this plant almost useless in Phoenix.
