5 Types of Hydrangeas You Should Never Cut Back in the Fall

Pruning hydrangeas at the wrong time can inhibit future growth.

Hydrangeas are known for being hardy plants, but pruning at the wrong time can inhibit future growth and vigor the next time they bloom. With that in mind, there are several types of hydrangeas you should never prune in the fall. Some hydrangeas bloom on old wood, which means the buds will appear on existing branches throughout the fall and winter. So, if you were to prune the shrub heavily in fall, you’re cutting off all the blooms for the next growing season. Below, we've rounded up some of the most popular hydrangeas that shouldn’t be pruned in fall, according to a gardening pro.

Meet the Experts

Lotte Berendsen , certified gardening expert for PlantIn , an app that helps gardeners identify plants and diagnose problems.

Related: How to Prune Every Type of Hydrangea (and When to Do It)

Bigleaf Hydrangeas

Prune your bigleaf hydrangeas ( hydrangea macrophylla ) before new growth appears in late winter or early spring. “After the flowers have turned brown in late summer, we recommend leaving them on until the end of winter,” says Lotte Berendsen, a certified botanist from PlantIn app. During the winter cold and frost, the spent blooms act as protection for the young buds that appear on the plant. “When the time comes to prune, we recommend trimming all the dead, spent flowers down to the last healthy set of leaves,” says Berendsen. Avoid pruning too heavily because this can also impact the plant’s growth.

Oakleaf Hydrangeas

The best time to prune oakleaf hydrangeas ( hydrangea quercifolia ) is in summer—around June to July—right after the flowers finish blooming. “If you prune in the fall, you’ll significantly impact next year's growth by accidentally removing many new buds,” Berendsen says. Moreover, this plant doesn’t typically need pruning very much. “Unless your oakleaf is extremely overgrown, heavy pruning is not needed for this shrub,” she says. Remove all the dead branches, making sure to remove no more than a third of the plant’s total size to keep it happy and healthy.

Mountain Hydrangeas

Like bigleaf hydrangeas, leave your mountain hydrangea’s ( hydrangea serrata ) blooms on the plant until spring. Doing this will help protect young shoots and buds. “We recommend removing dead and old wood [old shoots] from the shrub right before the growing season begins, at the end of winter or the very start of spring,” says Berendsen.

Panicle Hydrangeas

Panicle hydrangea ( hydrangea paniculata ) is a popular variety known for being incredibly cold hardy. The shrub is an upright grower whose branches typically arch under the weight of its large conical flowers. This variety should be pruned in late winter to early spring by removing spent flowers and pruning to improve the plant's structure and size.

Climbing Hydrangeas

Prune your climbing hydrangeas ( hydrangea anomala ) in the summer after the plant has bloomed. “These plants don’t need heavy pruning,” says Berendsen. Just remove the dead or spent flowers and branches.

Read the original article on Martha Stewart .