Flowering shrubs and small trees are a staple of most garden designs, as they provide height, structure, screening, and year-round interest. However, integrating these woody plants with perennials and annuals can be challenging because, over time, they will overtake their herbaceous neighbors. At Coastal Maine Botanical Gardens, where I am executive director, one technique we use involves managing smaller woody plants much as we do perennials: cutting them back severely every one to five years (the frequency depends on the variety).
Q: On my deck I have two birch trees in big planters, which have done well for many years. Now I’m beginning to worry about them. I prune them every year, but is it time to repot them or prune their roots? — Jay Cohen, Brooklyn, N.Y.