Flowering shrubs · pruning calendar
When to prune lilacs
Prune lilacs right after they finish blooming. They set next year’s flower buds soon after, so any later cut removes next spring’s flowers.
Lilac pruning by month
| Climate | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Coldzones 3–5 | January: Don’t prune now | February: Don’t prune now | March: Don’t prune now | April: Don’t prune now | May: Don’t prune now | June: Prune now | July: Don’t prune now | August: Don’t prune now | September: Don’t prune now | October: Don’t prune now | November: Don’t prune now | December: Don’t prune now |
| Temperatezones 6–8 | January: Don’t prune now | February: Don’t prune now | March: Don’t prune now | April: Don’t prune now | May: Prune now | June: Prune now | July: Don’t prune now | August: Don’t prune now | September: Don’t prune now | October: Don’t prune now | November: Don’t prune now | December: Don’t prune now |
| Warmzones 9–11 | January: Don’t prune now | February: Don’t prune now | March: Don’t prune now | April: Prune now | May: Prune now | June: Don’t prune now | July: Don’t prune now | August: Don’t prune now | September: Don’t prune now | October: Don’t prune now | November: Don’t prune now | December: Don’t prune now |
- Prune now
- Wait
- Don’t prune now
- Don’t prune now Next spring’s flower buds are already on the branches. Cutting now removes them.
- Don’t prune now It is about to bloom or blooming. Pruning now cuts off this spring’s flowers. Cut a few for a vase instead.
- Prune now Blooms just finished. This is the one safe window before next year’s flower buds form.
How to cut: Snip spent flower heads back to a pair of leaves. On older shrubs, remove up to a third of the oldest, thickest stems at ground level.
Sources
Months are grouped into broad USDA zone bands, so local weather, elevation and the plant itself still have the final say.
Free · no account · printable