Bottle Brush (Callistemon species) have commonly been referred to as bottlebrushes because of their cylindrical, brush like flowers resembling a traditional bottle brush. They are mostly found in the more temperate regions of Australia, especially along the east coast and typically favour moist conditions so when planted in gardens thrive on regular watering. At least some species are drought-resistant and some are used in ornamental landscaping elsewhere in the world. Once established, however, it is able to tolerate extended dry periods. It can tolerate less than perfect drainage but may be damaged by moderate to heavy frost.1. It appears to be mildly invasive, usually found spreading from an adjacent or nearby planted population. Plant with caution. Methods of invading natural areas: Humans have dispersed this plant globally for landscaping and cultivation. Seeds then travel over shorter distances from initial plantings through gravity or perhaps by wildlife. Habitat types it invades: wetlands and riparian areas that are adjacent to cultivated areas.