The breathtaking blooms on hydrangea shrubs are a gorgeous addition to any garden. Learning how to prune hydrangeas—and when to prune hydrangeas—starts with knowing which type of hydrangea you have.
Types of Hydrangeas
Old Wood vs. New Wood
These hydrangea terms refer to which stems produce the blooms. Old wood means the flowers appear on stems that grew last season, and new wood means that flowers appear on stems that grow this season. How you should be pruning hydrangeas depends on which kind of stems they bloom on.
Hydrangeas That Bloom on Old Wood
- Bigleaf: This H. macrophylla group of colorful hydrangeas with blue, pink and purple flowers includes Lacecap, Mophead and Mountain varieties. (We love the Wee Bit Giddy hydrangea!)
- Oakleaf: H. quercifolia hydrangeas are distinguished by the large foliage that resembles oak leaves.
- Climbing: The gorgeous, vining H. petiolaris hydrangea can reach heights of up to 60 feet.
Hydrangeas That Bloom on New Wood
- Panicle: H. paniculata hydrangeas have cone-shaped clusters of white flowers, with some varieties like Vanilla Strawberry fading to shades of red and green.
- Smooth: Varieties of the H. arborescens group include Annabelle and Incrediball with large, mounding flower heads.
How to Prune Hydrangeas
Pruning Old Wood Hydrangeas
These hydrangeas need minimal pruning: Just cut away dead, sickly or broken branches as needed. You can also remove faded blossoms by cutting the stem with sharp garden shears below the flower at a leaf node. There may be new leaves forming below the flowers, so take care not to damage these. Prune these hydrangeas only up until mid-August. As fall approaches your hydrangeas will create buds for next year’s flowers, and you don’t want to accidentally cut these off.
Editor’s Tip: Pruning hydrangeas in early spring helps the shrub produce more flowers, though the clusters will be smaller. Use sharp pruning shears to angle-cut an inch or so off the branch tips.
Pruning New Wood Hydrangeas
These hydrangea flowers appear a little later, starting in mid-summer. The best time to prune them is in late winter or early spring, when their leaves first begin to appear. For panicle hydrangeas, cut branches back by half or a third, at an angle just above a leaf node. Pruning this way helps keep the shrub height and shape in control. Or let the shrubs grow freely and prune only every two to three years to remove older or dead branches.
For smooth hydrangeas, you can prune them the same way as panicle types, although some gardeners choose to cut them down to the ground. Doing so will make the shrubs produce larger flowers, but the stems will be weaker and more prone to flopping over. Learn how to protect shrubs from heavy snow.
Typical hydrangeas produce one set of flowers per season, but there are some reblooming types like Endless Summer. They produce blooms on old wood and then again on new wood. These don’t need any pruning except as necessary to remove dead or diseased branches.
How to Know When Hydrangeas Are Done Blooming
You’ll know that the hydrangea blooms are finished when the colors of the flowers, whether blue, pink, green or white, have faded to brown. The flowers will have a papery texture and the cluster will feel stiff. You can deadhead the flowers at this point to tidy the shrub—but unlike other flowering plants, deadheading won’t produce new sets of flowers. You can also leave the dried flowers on the shrub for visual interest during fall and winter.
Speaking of the colder months, this is how to get your garden ready for fall.
Tools You Need for Pruning Hydrangeas
via homedepot.comGarden Gloves