My white butterfly bush is about 12′ high; I think it needs pruning bad. Can I do it now, and how much pruning can I do, drastically?
The Gardener’s Answer
Hello, Christiane: Butterfly bushes (buddleia) are easy, low-maintenance plants that are certain to attract butterflies and even hummingbirds. The best time to prune these shrubs is now (late winter/early spring) before they put on any new growth. Cutting them back in the late summer or fall will make any new tender growth very susceptible to frost damage. Pruning our plants encourages them to put on new growth. Butterfly bushes bloom on new wood (current season’s growth) so they can be pruned back hard, but avoid removing any woody growth. Ideally you want to cut it back to around 12 inches. This will encourage larger flowers as opposed to not pruning at all. Butterfly bushes are woody near the base of the plant, but produce new herbaceous growth year after year, which is why they are technically classified as a sub-shrub. Before you prune, be sure that your tools are clean and sharp. Later on in the summer as your plant blooms and the flowers fade, it is a good idea to remove the spent flowers. This will promote the plant to continue blooming throughout the season and into the fall.