Callistemon (Bottle Brush)
Callistemon are evergreen shrubs with aromatic, linear to lance-shaped leaves and bottlebrush-like spikes of flowers in which the long colourful stamens are prominent.
It's a very versatile plant and perfect as specimen in the lawn, against a wall or fence, or stunning planted in large pots as a tropical feature on the patio.
Height: In its native habitat, Callistemon citrinus is a large shrub, growing up to 16 ft (5 m). However, contained to a pot, it is easily kept to 4 ft (1.2 m) indoors. Yearly pruning will keep it compact. C. citrinus 'Little John' is a dwarf bottle brush variety, reaching only 3 ft (90 cm) tall.
Light: Full sun. Plants that don't bloom aren't getting enough light. Give Bottle Brush Plant as much light as you can year-round. A sunroom or a sunny spot directly in front of a window is ideal.
Water: Water thoroughly spring through fall and allow the soil to dry out between waterings. Reduce watering in the winter, while Bottle Brush plant is resting. It's drought-tolerant, so if in doubt about watering, keep it on the dry side. Yellow leaves are a symptom of overwatering and may indicate root rot.
Humidity: Average indoor (around 40% relative humidity). It will tolerate dry air.
Temperature: Average room (65-75°F/18-24°C). It's hardy in USDA Zones 9-10, so it can take the summer heat. Give it a cool rest in winter with a minimum temperature of 45°F/7°C.
Soil: Well-drained soil. Use 2 parts all-purpose potting mix and 1 part horticultural sand.
Fertilizer: Feed monthly spring and summer with high-potassium liquid fertilizer diluted by half.
Propagation: Take 3 in (7 cm) stem tip cuttings in spring or early summer. Can also be sown by seed in spring.