A butterfly bush quickly fills in space in the garden and require little care to grow tall and flower proficiently. Annual maintenance will increase the health and look of the plant. As flowers and trees start to die back in the fall, you'll know it's time to prune and mulch your butterfly bush to extend its life and increase flower size and productivity the following year.
Clip back the stems of the bush to only 4 inches tall if you live in a southern region with mild winters and normally above-freezing temperatures. Make a horizontal cut with your hand pruners.
Cut the entire bush back to the ground if you live in a northern region where the butterfly bush normally dies back completely over the winter and temperatures stay below freezing.
Add mulch around the base of the butterfly bush 2 to 3 inches deep after the first frost to insulate the roots of the plant over the winter months.
Watch for new growth in the spring. Provide an annual treatment of slow-release granule fertilizer when new growth sprouts.