How to prune butterfly bush

Early spring, just as new basal growth begins (late February–April depending on climate). Cut all main stems back hard to 12–18 inches above ground level using loppers or pruning saw. Remove any dead or crossing stems entirely. Deadhead spent flower spikes through summer to extend blooming.

Annually (hard spring cut); deadhead repeatedly through the flowering season. Butterfly bush blooms on new wood, so hard pruning in early spring drives the best flowering. Cut all stems back to 12–18 inches from the ground. Without pruning it becomes leggy and flower quality declines sharply. In many regions it is also invasive — deadhead spent spikes promptly to prevent self-seeding.

Cut all main stems back hard to 12–18 inches above ground level using loppers or pruning saw. Remove any dead or crossing stems entirely. Deadhead spent flower spikes through summer to extend blooming.