When is the best time to prune my butterfly bush?
Since this is considered an invasive plant, it is important to prune off all flowers as soon as they fade and before they set seed.
Since this shrub blooms July to August, it is pruned hard in March to early April. You want a strong base with all new shoots coming out. Keep new shoots pruned out as needed to maintain an open look. You can also prune back of all the main shoots by 1/3 in October if desired.