If left untended, common buttonbush could grow as high as 20 feet. An ideal height for the buttonbush as a landscaping plant would be 6-8 feet, naturally spreading as high as the plant is tall. Cutting back to control size and shape does not damage the plant--severe pruning stimulates new growth.
Keep the buttonbush's size controlled by pruning back branches in spring. Work before the plant shows new growth. With pruning shears clip the branch tips back several inches to reduce both height and diameter. Extensive pruning will not damage the plant's health but could reduce the spring bloom. Cut twigs back only as far as the last pair of leaf scars.
Clean up the shaped bush with pruning clippers, removing the stubs of cut twigs to within an inch of the next leaf scars on the branch. With clippers or limp loppers cut out any dead or damaged branches. Use limb loppers to remove overlapping limbs by cutting off the least vigorous branch just above the bark of the trunk.
Set the ladder as close to the trunk as possible before working on the upper part of the bush. Correctly positioning the ladder lets you face the tree as you stand on the ladder's lower steps. Use loppers and pruning shears to reduce the height of the bush and shape the top branches. Move the ladder as necessary to work safely.
Comb loose trimmings from the branches of the buttonbush with the rake. Rake clippings from beneath the bush and place debris--old leaves, new clippings and last year's seed pods--into the cart or wheelbarrow. Buttonbush debris could be safely composted or burned since the bush has no major diseases or pest problems.
Except for removing storm damaged branches do not prune the bush during the growing season. With limb loppers, remove the damaged section of limb by cutting just below the injury. If the limb dies back later in the year, lop the dead wood off at the next healthy junction.