Finch sitting on a bottlebrush branch
Stable

Bottlebrush

Callistemon sp.

 

Bright Red Brushes

An evergreen tree or shrub native to Australia, the bottlebrush is well known for its graceful, drooping branches ending in flowers with cheerful, bright red or yellow stamens, which form in tufted clusters that resemble a round brush. They have that in common with their close relative, the paperbark tree Melaleucasp., which bears similar flower spikes. Although most bottlebrush are about 5 to 12 feet (1.5 to 3.7 meters) tall, some mature trees can reach more than 30 feet (9 meters) in height.

Characteristics

Flowers

The actual flowers of the bottlebrush are the tiny, creamy white nubs close to the stem. They form as buds in cylindrical clusters surrounding the stem. When they bloom, the petals open to reveal long, colorful stamens, each tipped with an anther bearing yellow pollen. The collection of all these flowers with their bright red stamens densely packed around the stem is called the flower spike—the distinctive “bottlebrush” that people know so well.

Although the flower spikes of most bottlebrush are red, their color can be bright purple, pink, red, yellow, white, or green. These colorful flower spikes typically appear in the spring and summer, and they attract nectar-feeding birds and insects. They are a particular favorite of bees and hummingbirds. As they feed on the flower’s nectar, they transfer pollen from the anthers of one flower cluster to the stigma found at the center of another flower cluster, pollinating the plant.

Fruits and Seeds

The flowers are not just showy bursts of color—when pollinated, they produce small, woody fruits that contain hundreds of tiny seeds. These fruiting capsules form in bunches along the stem, and they are usually held on the plant for many years. Bottlebrushes take a long time to release their seeds, from a year to several years. Some even require fire to stimulate the capsules to open.

Leaves

While the flower spikes are the most noticeable part of the bottlebrush, the leaves are attractive as well. They are usually dark green and covered with soft, fine “hairs” that help collect moisture. To help protect the plant against heat and dry periods, the leaves are long, thin, and tough and don’t lose much water through evaporation. The leaves are aromatic, covered with tiny oil glands that release a mint or menthol scent.

How to Use a Bottlebrush

With their bursts of bright color and long-lasting flowers, bottlebrushes are often used in floral displays. They are also one of the most popular garden plants used in the United States, and they make a great and prolific addition to pollinator gardens. Although they originate in the Land Down Under, they are a staple in California landscaping, since they are hardy, drought resistant, and easy to care for.

The larger and taller varieties of bottlebrush develop hard, heavy, and tough wood that can be used as fuel, or to make fence posts because the wood resists rot. Surprisingly, bottlebrush are also mentioned in a 19th century handbook of Australian plants as a source of lumber: the lemon bottlebrush Callistemon pallidus is recommended for ship building, wheel-wright’s work, and mallet handles.

Some Types of Bottlebrush

Prickly Bottlebrush

Callistemon brachyandrus

This prickly leaved shrub grows to about 9 feet (2.7 meters) and is an excellent plant for hot, dry areas. The tips of the small red flower spikes are covered in yellow pollen.

Crimson Bottlebrush

Callistemon citrinus

This hardy shrub is probably the best known bottlebrush and is widely cultivated. Crimson bottlebrush grows well in wet soil conditions and usually reaches 13 feet (4 meters).

Kingaroy Bottlebrush

Callistemon formosus

This attractive shrub is suitable for tropical and frost-free areas. Plants grow to 9 feet (2.7 meters) and have graceful, drooping branches. The flower spikes are yellow instead of red, and are produced throughout the year. It gets its common name from being planted along the streets in Kingaroy, Queensland, Australia.

Lemon Bottlebrush

Callistemon pallidus

A tough, frost-tolerant bottlebrush that grows well in most soil conditions. As its common name suggests, its flower spikes are yellow, and they emerge in summer.

Alpine Bottlebrush

Callistemon pityoides

This very hardy and attractive bottlebrush is available in several forms. The alpine form grows as a compact bush to about three feet tall, while other forms grow as erect shrubs to about 6 feet (1.8 meters) tall. Its yellow flower spikes are produced in spring and summer.

Willow Bottlebrush

Callistemon salignus

This bottlebrush grows like a tree and can reach between 15 and 30 feet (4.5 and 9 meters) in height. It is drought resistant and hardy and has attractive, narrow foliage and white, papery bark. The flower spikes are typically white, cream, or light green, but pink, red and mauve varieties can be found.

Dwarf Bottlebrush

Callistemon subulatus

This compact shrub grows from 3 to 9 feet (1 to 2.7 meters) tall and is able to tolerate wet soil conditions. The summer-blooming flower spikes are a bright red.

Weeping Bottlebrush

Callistemon viminalis

This large bottlebrush is widely cultivated for gardens and landscaping. It grows 15 to 30 feet (4.5 to 9 meters) tall and produces bright red flower spikes that are rich in nectar and attract birds. This variety is not as drought tolerant as other bottlebrushes, and needs enough water to keep the soil consistently moist.

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Sounds

Filamental, My Dear

The bottlebrush genus name Callistemon means “beautiful stamen,” in tribute to the well-known long, dense tufts of red stamens—also known as filaments—emerging from the flowers.

A Bright Import

The popularity of the cheery bottlebrush started in 1789, when Joseph Banks imported the crimson bottlebrush Callistemon citrinus from Australia to Britain.

 

It's in the Bark

In Australia, bottlebrush trees sometimes host cossid moth larvae, known as witchetty grubs—a popular food for Aboriginal Australian people.

 

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