Gardening matters: the brilliance of bottlebrushes

Callistemon: 'Little John' or bottlebrush, part of the Myrtaceae family.
Callistemon: 'Little John' or bottlebrush, part of the Myrtaceae family.

In a horticultural popularity contest the bottlebrushes (callistemons) and grevilleas would probably vie for the top position.

This time we will concentrate on the bottlebrushes. Most bottlebrushes develop into medium to tall shrubs. A few varieties grow into mounded ground covers whilst a small number reach tree size.

The crowning feature of the bottlebrushes is their colourful flower spikes. Red, pink, cream white and green are some of the colours in the bottlebrush flower palette. Each brush is composed of a large number of individual flowers. The blooms are rich in nectar and when gathered in a spike they are more attractive to honeyeaters and insects than individual flowers.

In the wild most bottlebrushes grow along watercourses and other moist areas. In cultivation they survive, thrive and bloom bounteously in dry, well drained sites.

Bottlebrushes are virtually free of problems. An annual pruning is the only maintenance required. Once spikes fade cut them off. This will prevent plants from becoming straggly and increase flower production.

Most bottlebrushes flower in late spring and summer. They take over flowering, in the garden, after the spring bloomers have finished.

Callistemon “Little John” is one of the few small bottlebrushes. This cultivar is a dwarf, rounded shrub measuring a metre high by a metre wide.

The leaves are narrow, an unusual blue-green colour and crowded on the stems. Flower spikes are dark red and appear, in large numbers, during spring and summer. Honeyeaters enjoy visiting the flowers. Both foliage and flowers are attractive features.

“Little John” would make a colourful foreground specimen in a native shrubbery.

Callistemon pinifolius, the Pine-leaved Bottlebrush, is an open shrub that will reach a height of two metres with a similar spread. The leaves are narrow, about ten centimetres long with a sharp point (hence the common name).

One form has lime-green flowers, the other is red.

The unusual lime-green form is particularly attractive. In both cases the spikes are about eight centimetres long. Blooms appear in late spring or early summer.