Compared with the pruning guidelines for many shrubs and trees, hydrangeas’ pruning needs are pretty minimal. Most need very little actual pruning. They’re fine with just enough of a trim to shape the plant, get rid of dead branches and encourage future blooms.
If you know what type of hydrangea you have, check below for the recommended pruning guidelines. If you’re not sure, you’ll need to know whether your hydrangea blooms on old wood or new wood before you take to the shrub with a pair of clippers.
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Know the basics
There are two simple rules of hydrangea pruning. If it blooms on old wood, you prune after the flowers fade in the middle of summer, otherwise you wait until late winter or early spring. And if it blooms on new wood, then late winter or early spring is the optimal time to prune.
New wood versus old wood
To understand what gardeners mean when they talk about old and new wood, take a look at your plant while it’s in bloom. If the flowers are on stems and branches that appeared on the plant during the previous year or years, then that species of hydrangea blooms on old wood. If the flowers are clustered on new stems and branches that first appeared in the early spring of the current year, then your plant blooms on new wood.
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