What is the best time to prune Butterfly Bush?
The optimal time to prune a Buddleia davidii (Butterfly Bush) is late winter or early spring. Cut back, using a sharp sterilized instrument, to the 2nd or 3rd buds from the base of the previous years growth. Only prune older wood in order to reshape the shrub or remove branches that are dead or diseased. Buddleias are shrubs (hardy only to zone 5, where they might die back an go dormant) that bloom late in the season on new growth so pruning in the spring will not hamper flowering but will encourage a stronger, more vigorous plant.