Grow bottlebrush (Callistemon) trees for their colorful bottlebrush-like spikes available in red, pink, purple, white, yellow or green varieties. This subtropical tree, native to Australia, grows to heights between 6 and 15 feet high. When to prune typically depends on personal preference as bottlebrush trees can be trained or left to grow.
Get underneath the tree and start cutting from the inside.
Cut primarily the branches near the trunk. It's best to cut inside branches as they contain more dirt and insects and receive less sun so they are generally less healthy.
Cut on the leaf node just above a row of seedpods, if any are present. Clip with sharp, clean garden shears. When cutting, stand back after you cut a few branches to look at the tree and make sure it does not appear too thinned out.
Clip off lower forked branches. Only cut off the lower inside branch.
Prune the bottlebrush tree throughout the season whenever inside branches appear heavy. Stop pruning as fall approaches to protect against cold damage to newly pruned, exposed branches.
Water after pruning to nourish the tree and revive it from the trauma of pruning. Spray water at soil level to protect raw wounds.