Answer: Coneflowers and black eyed Susans are not usually pruned before they bloom. Fall blooming asters on the other hand often benefit from being pinched or lightly sheared two or three times between early spring and mid summer. This helps keep them a bit denser and shorter. You might nip off the top six inches on the asters since they are already so tall. Allow them to grow about six inches and tip them very lightly once.
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