What shrubs should I prune in summer in NB?

Summer pruning in New Brunswick is specifically for shrubs that bloom on new wood (current year's growth) and should be done in late June through July after their spring flush of growth.

The main shrubs to prune during summer in NB include hydrangeas (Annabelle, PeeGee, and panicle types), spirea (summer-blooming varieties like Goldflame and Anthony Waterer), potentilla, rose of Sharon (hibiscus), and butterfly bush if you're growing it in a protected Zone 5 location. These shrubs benefit from summer pruning because they'll produce flowers on the new growth that emerges after cutting.

Summer pruning timing in New Brunswick is critical due to our short growing season. Prune these shrubs in late June through mid-July, after their initial spring growth surge but with enough time for new shoots to mature before our early fall frosts. This gives the plants 8-10 weeks to develop new flowering wood before growth slows in late August. Never prune after early August in NB, as late-season growth won't have time to harden off properly for winter.

For hydrangeas specifically, this applies to smooth hydrangeas (Annabelle types) and panicle hydrangeas (PeeGee, Limelight). These can be cut back by one-third to one-half in summer. However, avoid summer pruning of bigleaf hydrangeas (the blue/pink mophead types) - these bloom on old wood and should only be pruned immediately after flowering in late summer, if at all, since they're marginal in most of NB anyway.

Avoid summer pruning of spring-flowering shrubs like lilac, forsythia, mock orange, and flowering quince. These bloom on old wood, so summer pruning removes next year's flower buds. Also skip summer pruning of evergreens - they're best pruned in late winter or very early spring in NB.

When summer pruning, make clean cuts just above outward-facing buds, remove any dead or crossing branches first, and don't remove more than one-third of the shrub's total growth in a single season. In NB's humid Maritime climate, clean cuts heal better and reduce disease risk.

Need help identifying which shrubs to prune when? A local landscaper can assess your specific plants and create a seasonal pruning schedule. New Brunswick Landscaping can match you with experienced local professionals who understand NB's unique growing conditions and timing requirements.