When plants contain some overgrown branches on it which becomes less vigorous due to spreading of pesticides,resulting in poor display of flowers.Such plants are pruned i.e. cut regularly to maintain an attractive shape and to prevent them from any damage or disease.

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I prune my heathers annually in early spring, cutting off most of the flower tracts. It will green up again in late spring and show new flowers later. Do not cut into wood or the plant will not grow green leaves and flowers on that wood.

Over time heathers might become too large, and you then can dig out the plant and plant it deeper, also amending the soil with peat moss.