Scientific: Melaleuca citrina (also referred to as Callistemon citrinus). Callistemon lanceolatus is an old scientific name.

A scientific name quagmire: Lyn Craven of the Australian National Herbarium (Novon 16 468-475; December 2006 “New Combinations in Melaleuca for Australian Species of Callistemon (Myrtaceae)”) argued based on genomic research that the differences between the two genera, and Melaleuca are insufficient to warrant them being retained separately and that they should be combined, thus Melaleuca is the preferred genus based on earlier precendence.

Common: lemon bottlebrush
Family: Myrtaceae
Origin: Coastal New South Wales, Victoria and southern Queensland of Australia, usually in bottomland swampy sites.

Pronounciation: Mel-a-LOU-ka ci-TRI-na

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, upright, stiff and brittle.

Growth Habit: Upright, 8 to 15 feet, 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 inches 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; suffers during summer if temperature exceeds 112oF for extended periods.

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: Lemon bottlebrush shrubs (citrina means lemons scented) strongly attracts bees when in flower. This species has been responsible for many of the bottlebrush cultivars that are seen in landscapes today, sometimes as hybrids with other Melaleuca (formerly Callistemon) species. Most of these cultivars have arisen as chance seedlings rather than by deliberate hybridization. Some of the better known marketed cultivars of M. citrina are 'Mauve Mist' (mauve), 'Burgundy' (purple-red), 'White Anzac' (white), 'Endeavour' (red) and 'Reeves Pink' (pink). In the end though, leaf chlorosis (yellowing) caused by high soil alkalinity and salinity makes this plant almost useless in Phoenix.