Callistemon viminalis - Bottlebrush

Callistemon viminalis is undoubtedly the most widely planted Bottlebrush in the world. This small bush, with its beautiful ornamental qualities, has a graceful weeping habit, fine and elegant evergreen foliage, and a dazzling spring flowering in the form of particularly bright red bottlebrushes. It is a fairly adaptable species in cultivation, valuable for landscaping in mild climates. It can be planted in rows to form a screen, or even as a solitary specimen in a small garden. It is also a good conservatory plant in colder climates.

Callistemon viminalis, also known as Weeping Bottlebrush, is a large shrub from the myrtle family, related to myrtles and Leptospermum. It is native to southeastern Australia, specifically New South Wales and Queensland, where it is frequently found growing along watercourses in partial shade. In its natural environment, it can reach a height of 15 m (49 ft 2 in), but in colder climatic conditions, it rarely exceeds 7 m (23 ft) in height and has a spread of 2 to 3 m (6 ft 7 in to 9 ft 10 in).

It is an evergreen shrub in mild climates, with brittle wood, forming a dense dome-shaped crown composed of trailing branches. It has a relatively fast growth rate. Its linear and narrow leaves are divided into leaflets measuring 2 to 8 cm (0.8 to 3.1 in) in length, with a beautiful green-grey hue. In spring, young shoots tinged with red emerge at the tips of the branches. Its axillary flowers are composed of very long bright red stamens, which take on a more magenta hue as the days go by. They are arranged in cylindrical spikes at the tips of the flexible young branches. These inflorescences are about 5 cm (2 in) in diameter and 7 cm (2.8 in) in length, and they hang slightly. The terminal bud repeatedly produces new leaves and then new bottlebrushes, while the old inflorescence produces small cup-shaped fruits. Flowering can occur several times during the season in moist soil and hot climates, especially in late summer. Its grey-brown bark is fissured and decorative. It is also a honey and nectar plant that attracts many pollinating insects to the garden.

Hardy to about -5 °C/-6°C (21.2 °F), Callistemon viminalis tolerates summer drought once well established, but appreciates water in dry climates. In a greenhouse or conservatory, it can be combined with an orange tree, a Tibouchina, or a mimosa to create an extremely decorative quartet, evoking landscapes with exotic charm and fragrances. In mild climates, it can be used as a solitary specimen – it deserves it – in a free-standing hedge or at the back of a border, even on the edge of a woodland. It can also be planted in an evergreen hedge, accompanied by a shrubby ceanothus ('Italian Skies', 'Concha', 'Puget Blue', 'Skylark', etc.), a spring-flowering broom, or oleander ('Soleil Levant' or 'Provence'). Its good tolerance to salt allows for coastal exposure, facing wind and sea spray.