Experts and BHG readers answer.
How do we rejuvenate old holly bushes?
Hollies can be drastically pruned, and mid-winter is the best time to do so. However, you should determine why the trees became leggy and scraggly in the first place. Are they getting too much shade, or is it simply aging of the plant? If excess shade is part of the problem, you'll need to prune surrounding trees and shrubs, too, or the new growth will get leggy immediately and never fill in completely. Although holly can resprout from a severe cut back, it's best to prune only back as far as green leaves exist on the plant. Pruning more severely (that is into very old wood) may result in little new growth.