One of the more time sensitive tasks of garden editing is the pruning of trees and shrubs. In general trees and shrubs should not be pruned after late August. Late summer pruning oftentimes promotes new growth and new growth late in the growing season is susceptible to winter injury.
I do a bit of last minute shaping this time of year and hand prune those errant branches that shoot out beyond the main growth of the shrub. Azalea, viburnum and weigela are a few that require a little attention. I leave any serious pruning now until after we have had a few hard frosts and the plants are truly dormant.
Deciduous and evergreen trees and shrubs can be pruned all winter long and the task is made easier in the absence of perennials and annuals in the garden. Exceptions to winter pruning include rose bushes, mophead, oakleaf and climbing hydrangea and spring flowering trees and shrubs.