Fall vs. Spring Pruning for Knockout Roses in Cold Climates (Zone 5)

A Montreal gardener (zone 5) pruned their Knockout to 18 inches last fall before snow. Two main canes were part brown/green and didn't grow, so they were cut. They asked about fall pruning and making the plant more upright.

Don't Prune in Fall

In cold zones, fall pruning removes cane length that buffers winter dieback. Wait until spring, then prune past any dead wood. This preserves the plant's energy and structure.

Upright Habit

Hard spring pruning encourages strong, upright new canes. Knockout roses respond well to severe spring cuts.