Common Mistakes To Avoid When Pruning A Butterfly Bush In The Spring

Butterfly bushes (Buddleja davidii) are known as one of the best plants to attract a variety of butterflies to your yard thanks to their large, nectar-filled flowers. As a bonus, their pink-purple blooms are truly stunning. Although butterfly bushes are relatively easy to care for, they need basic maintenance, such as pruning, to ensure they can thrive.

Though it sounds simple, it's easy to make mistakes when pruning a butterfly bush. Two of the biggest potential errors are trimming the bush too early and not pruning it enough. Buddleia davidii is extremely hardy and can handle a thorough pruning, but many gardeners do it wrong and end up with excessively tall bushes.

Thanks to its hardiness, butterfly bush is a prolific spreader and is considered invasive in several states on the Eastern Seaboard and in the Pacific Northwest. Growing the butterfly bush in these areas could damage local ecosystems. If the plant is invasive in your area but you love its appearance, look for seedless and non-invasive varieties, which are often sold under the name "summer lilac" instead of "butterfly bush." 

Butterfly bushes may be hardy, but they're not immune to damage and disease. Pruning the plant in the fall or early winter rather than early spring can cause ice to form inside the hollow stems and damage the wood. To prevent this issue, cut back your butterfly bush once the last frost has passed and buds start to form on the stems. 

Another common mistake is not pruning your butterfly bush enough. This tough shrub can handle being trimmed back to 12 to 24 inches in height, even when it's young. If you prune too little, the flowers can grow too high on the bush, making them harder to see and appreciate. For the best results, cut the branches just above the new buds.

Butterfly bushes can grow in various climates and aren't fussy about soil quality, though they prefer full sun and a well-drained growing medium. Caring for a butterfly bush means frequent watering to keep the soil moist. Also, deadheading is a must once they finish blooming to make way for new flowers.