The Six Types of Hydrangeas
Knowing your hydrangea type is critical because pruning rules depend entirely on which type you have. Prune the wrong type at the wrong time and you lose an entire season of blooms. The six types differ in flower shape, bloom timing, and whether they flower on old wood (last year’s growth) or new wood (current year’s growth).
| Type | Flower Shape | Blooms On | Prune When | Zones |
|---|---|---|---|---|
| Bigleaf (mophead/lacecap) | Round mophead or flat lacecap | Old wood | Right after bloom (July to August) | 5 to 9 |
| Panicle (PG) | Cone-shaped (football) | New wood | Late winter (Feb to March) | 3 to 8 |
| Oakleaf | Cone-shaped, oak-shaped leaves | Old wood | Right after bloom | 5 to 9 |
| Smooth (Annabelle type) | Large round, white/green | New wood | Late winter | 3 to 9 |
| Climbing | Flat lacecap | Old wood | Right after bloom | 4 to 8 |
| Mountain | Flat lacecap, compact | Old wood | Right after bloom | 5 to 8 |
Bigleaf Hydrangeas (Hydrangea macrophylla)
The most popular type, including mophead (round flower clusters) and lacecap (flat clusters with tiny flowers surrounded by larger petals). Bigleaf is the ONLY type whose flower color changes with soil pH: acidic soil produces blue, alkaline soil produces pink. They bloom on old wood, meaning flower buds form in late summer and fall on this year’s stems for next year’s bloom. Pruning at the wrong time removes those buds.
The Endless Summer series (‘Endless Summer’, ‘Bloomstruck’, ‘Twist-n-Shout’) are reblooming bigleaf varieties that flower on both old and new wood, providing insurance against poorly timed pruning or winter bud kill.
Panicle Hydrangeas (Hydrangea paniculata)
Cone-shaped flower clusters that start white or green and age to pink. The most cold-hardy type (zones 3 to 8) and the easiest to grow. Blooms on new wood, so you can prune hard in late winter without losing flowers. Limelight, Little Lime, and Quick Fire are the most popular panicle varieties. These are the most forgiving hydrangeas for beginners.
Oakleaf Hydrangeas (Hydrangea quercifolia)
Named for their large oak-shaped leaves that turn burgundy-red in fall. Cone-shaped white flower clusters. The best fall color of any hydrangea. Blooms on old wood. Native to the southeastern US. Exfoliating bark provides winter interest. More sun-tolerant than bigleaf and better adapted to southern heat. ‘Alice’, ‘Snow Queen’, and ‘Ruby Slippers’ are popular varieties.
How to Identify Your Type
Check three things: leaf shape (round = bigleaf, panicle, smooth, or climbing; oak-shaped = oakleaf), flower shape (round balls = bigleaf or smooth; cones = panicle or oakleaf), and plant size (climbing reaches 30+ feet on walls, everything else stays 3 to 12 feet). If in doubt, check the plant tag or search the variety name. Getting this right determines your entire pruning approach.
