Trimming my new hydrangea tree

(Question)

This is the 1st year for my hydrangea tree as it was planted late last Fall. Early this Spring I cut back the dead branches. It is leafing out very nicely now but, I notice, I didn’t pay enough attention to pruning it evenly so one side is taller than the other side. It is late May now. Could I still try to shape the tree without damaging the tree or killing potential flowers.

(Answer)

 

Further pruning now should not damage the long term life of your tree.  That being said, the question of whether this year’s  potential flowers may have been “pruned off” depends on the type of hydrangea it is.  If it is a hydrangea that flowers on old wood then the pruning that you have already done this spring may inhibit flowering this year.  If this is the case then further pruning to even up the previous trim job will make your tree a better shape, but it may not flower this year. Pruning of hydrangeas that bloom on old wood should be done as soon as the blooms begin to fade.  This is usually mid-summer.  The longer you wait, the probability of cutting off next year’s blooms increases. The following from a previous  Master Gardener post may prove helpful:

There are many species of hydrangeas but they can be divided into two large groups, those that bloom on old wood and those that bloom on new wood.

The following is a list of the more common species and whether they bloom on old or new wood:

Species Cultivars Common name

New wood

Old wood

H. arborescens ‘Annabelle’

X

H. macrophylla* Mophead

X

H. macrophylla var. normalis Lacecap

X

H. paniculata PeeGee

X

H. quercifolia Oakleaf

X

* recently new H. macrophylla cultivars have been developed that bloom on old and new wood, like the Endless Summer Series and Let’s Dance Series.

Hydrangeas that bloom on new wood are a more reliable bloomer.  You can cut them back to the ground either in the fall or spring and they will bloom in the summer.

Judith King, a member of the American Hydrangea Society put a website together called: Hydrangeas, Hydrangeas! Which I find it helps with pruning techniques for each type and offers further general information:

https://www.hydrangeashydrangeas.com/identify.html