Bottle brush, or bottlebrush, is a shrub from Australia that produces red blooms. The shrub gets its name from the cylindrical bloom that resembles a brush used for cleaning narrowed-necked bottles, like baby bottles. Bottle brush grows best in damp locations, but some varieties have shown to be drought-tolerant. The shrub, which can reach a height of 12 feet, prefers full sun. Bottle brush can be grown in U.S. Department of Agriculture (USDA) cold hardiness zones 9 to 11. Most pruning can be done after the shrub stops producing flowers for the season.
Cut spent blooms close to the bloom.
Cut branches deep inside the shrub, close to the trunk, to open it up. Make the cuts on an angle above a leaf node. Cut off varying amounts of each branch; for example, cut 1/3 off the top of one branch and 2/3 off the next branch for a more natural appearance. Cut the lower branch when you come to a fork.
Cut stray branches that project out the sides or top of the shrub.
Cut off broken branches as they occur. Make the cut 3 to 6 inches from the break and above a leaf node.
Prune an overgrown bottle brush to the ground using loppers. This aggressive pruning can be completed anytime during the year.