Q. Can you suggest suitable trees and shrubs for containers for my Center City, Philadelphia garden?
Ray Rogers, author of the book Pots in the Garden ; expert design and planting techniques provides a very good list of suitable trees and shrubs ranging from Japanese maples (Acer palmatum ) to color-twig dogwoods such as Cornus sanguinea to Honeybush (Melanthus major) to various junipers.
The PHS McLean Library has both the print and eBook version of this book. Attached is a plant list from Pots in the Garden.