How to prune Hydrangea L. (Hydrangeaceae) paniculata Siebold and similar Hydrangea trees
So where do I prune the Hydrangea L. (Hydrangeaceae) paniculata Siebold tree and similar Hydrangea trees? Do I cut right beneath the faded summer bloom or deeper on the stem? What time of the year is best to prune them? Is it too late this year?
Prune in late winter to early spring. Prune out any suckers (growth coming up from the ground near the "trunk") and any growth along the main stem. Then prune the branches back to two or three nodes to keep the weight on these branches manageable.
This hydrangea can also be pruned all the way to the ground if you want a shrub look.
Here is a good description of pruning all kinds of hydrangeas. Remember that this is an Arkansas publication, and so some dates may be incorrect for our area and some of these hydrangeas won't grow in Minnesota.