09/06/2026
A shrub can look perfectly healthy and still refuse to bloom for an entire season. In many cases, the problem isn’t disease, pests, or fertilizer—it’s pruning at the wrong time.
The key is knowing whether your shrub flowers on old wood or new wood.
🌿 Old wood bloomers produce flower buds on growth that formed the previous year. Those buds are already in place long before spring arrives. If you prune too late, you remove the flowers before they ever have a chance to open.
Common old wood bloomers:
• Forsythia
• Lilac
• Azalea
• Oakleaf hydrangea
✂️ Pruning window: Immediately after flowering, ideally within 4–6 weeks.
🌿 New wood bloomers create flower buds on fresh growth produced during the current season. Because they bloom on new stems, they can be pruned before spring growth begins without sacrificing flowers.
Common new wood bloomers:
• Butterfly bush
• Panicle hydrangea
• Smooth hydrangea
• Knock Out® rose
✂️ Pruning window: Late winter to early spring. Many gardeners prune these shrubs hard to encourage stronger growth and larger flower displays.
Before reaching for the pruners, identify which type of shrub you're growing. A five-minute check can mean the difference between months of color and a season with no blooms at all.