Bottlebrush Plants: How to Grow Bottlebrush

Bottlebrush plants, common name Callistemon, are evergreen trees and shrubs native to Australia. Bottlebrush flowers, named for their resemblance to bottle brushes, are long clusters of pollen-tipped filaments that grow cylindrically along a multi-trunked base. Their leaves are small and green, with white, green, purple, yellow, or red flower spikes depending on the cultivar.

While bottlebrush trees can grow between twenty-five and thirty feet tall, there are also dwarf bottlebrush cultivars (like “Little John” bottlebrush) that will only grow around three feet tall. Bottlebrushes are nontoxic for humans and animals.

There are around forty species of bottlebrush shrubs and trees that produce blooms of varying hues. Here are some of the popular varieties of bottlebrush.

1. 1. Crimson bottlebrush (Callistemon citrinus): Crimson bottlebrush, whose common names include lemon bottlebrush or common red bottlebrush, is a lemon-scented bottlebrush (when the leaves are crushed), and can grow anywhere between three and twenty-five feet tall. They are deer- and drought-resistant.
2. 2. Prickly bottlebrush (Callistemon brachyandrus): This prickly-leaved shrub can grow up to ten feet tall and thrives in warm, dry climates. Its red, spiky flowers are punctuated with bright yellow pollen.
3. 3. Stiff bottlebrush (Callistemon rigidus): Stiff bottlebrush can grow between ten and twenty feet tall and prefers acidic, well-drained soil. These bottlebrushes are deer-resistant, and are hardy against other pests or diseases.
4. 4. Weeping bottlebrush (Callistemon viminalis): Weeping bottlebrush plants are known for their drooping (“weeping”) branches. They grow between twenty and thirty feet tall with a fifteen-foot spread and prefer loamy, sandy soil. They are both deer- and drought-tolerant.
5. 5. White bottlebrush (Callistemon salignus): Also known as the willow bottlebrush, this type of bottlebrush grows white brush-like flowers. Though these shrubs grow up to twenty-five feet tall and fifteen feet wide, they require little pruning, and are especially useful for hedges and landscaping.

Bottlebrush shrubs and trees need a temperate climate. In USDA hardiness zones 8b through eleven, they can be planted near year-round. However, if you live outside of these climates, plant your bottlebrushes inside in the late spring, a few weeks before the final frost has passed. By the time that the summer arrives, it will be warm enough to move your plants outside to soak up the warm weather.

Bottlebrush plants can be propagated from cuttings or grown from seeds. Here is an overview of how to propagate bottlebrush from seeds.

1. 1. Collect your seeds. To grow a new bottlebrush plant, you can harvest the seeds from an existing bottlebrush plant, which are contained inside of the woody fruits that sit toward the lower branches of the shrub. Place these fruits inside a brown paper bag and leave in a warm, dry location. After a few days, the fruits will crack open, and you can collect your seeds. Alternatively, you can also purchase seeds from a nursery.
2. 2. Prepare your soil. Bottlebrush seeds are best when they are fresh. You can sow seeds directly into your garden soil, or germinate them in a smaller pot to be transplanted into larger pots later on. Prepare your soil by loosening it a few inches deep, then thoroughly moisten the top. Make sure your planting area has good drainage.
3. 3. Sow your seeds. Sow your bottlebrush seeds directly onto the surface of the soil and water them immediately after. Keep your seeds and soil warm during the germination period by placing a plastic cover over the tray to maintain heat. Sprouting should take place within two weeks.
4. 4. Keep plants in a sunny location. Bottlebrushes need plenty of full sun, at least six hours of direct sunlight a day. Make sure you place your seedling tray in a place that receives full sun.
5. 5. Taper off your watering. Growing bottlebrushes need regular waterings to grow, but mature, established plants don’t need as much water. You can wait to water older plants until after the soil has dried out a little bit more.
6. 6. Prune your bottlebrush occasionally. Deadhead the spent blooms and lightly prune your flower blossoms shortly after they emerge. Trim back the inner branches and remove any dead or woody stems to make sure the interior of your area receives plenty of sunlight.
7. 7. Mulch. A two-inch layer of mulch will help you smother weeds and keep your soil moist, which can help you avoid overwatering.
8. 8. Fertilize. Fertilize the soil around the bottlebrush with a layer of compost after the second spring of growth. Move aside any mulch before applying, and keep the organic matter a few inches away from the stems.

Bottlebrushes make great landscaping hedges and shrubs, but you can also grow them indoors. Follow these tips to cultivate healthy, thriving bottlebrush shrubs.

1. 1. Choose the right variety. Different varieties of bottlebrush may have specific growing conditions. For example, some are more shade-tolerant than others. Make sure the kind of bottlebrush you want to grow can thrive in your chosen location.
2. 2. Use them to attract pollinators. You can strategically place bottlebrushes around your garden to help attract beneficial insects and critters such as hummingbirds, bees, and butterflies, which can aid in pollination.
3. 3. Incorporate dwarf varieties. Dwarf varieties of bottlebrush plants are slightly easier to manage. Use these diminutive varieties to create neat hedges, borders, and pathway linings for your yard.
4. 4. Provide adequate spacing. Some bottlebrushes have a wide spread, so you want to keep an adequate amount of space between each plant so they don’t crowd one another. Keep your plants at least five feet from the outer walls and windows of your home.
5. 5. Use tall varieties for shade. Taller bottlebrushes can give your smaller, shade-loving plants protection from the bright sun.

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