Q. When and how should I prune azaleas? The plants are leggy and open. I’d like for them to be fuller.
A. In pruning azaleas, it’s best to wait until the blooms have faded but before July.
Azaleas begin flower bud initiation in late summer to early fall. So, avoid pruning too late because you can either disrupt flower bud initiation or prune away the dormant flower buds.
The end result of pruning azaleas and other early flowering shrubs and trees too late is that you’ll end up with few to no flowers the following spring.
There are a couple of basic ways to go about pruning azaleas. You can quickly shape them with pruning shears, or you can take a little more time and strategically remove only the longer/taller shoots. The desired end result will help you make the decision as to which method to use.
If you want a more formal-looking plant, you may wish to shape the plant with shears. If you want a more natural-looking plant, you can just take out the taller shoots.
I usually prefer to mostly prune out the taller shoots through a series of thinning cuts. In doing this, I follow the taller shoots back into the plant and try to cut them where they originate. In other words, I prune them where they come out of another branch or the main trunk with hand pruners.
By doing this, I reduce the overall height without having to shear the plants. The end result is a more natural-looking plant instead of one that looks like a ball or box from being sheared.
It’s important to know that the new growth produced as a result of a pruning cut is produced a few inches below the cut. So, you’ll need to make strategic pruning cuts where you’d like the plant to fill in and be less leggy – remembering that new growth occurs a few inches below each cut.
You may need to come back after the new shoots are eight to twelve inches in length and prune them back to stimulate new growth if they are a little leggy and the plant is still too open and sparse. You should be able to do all this before July.
You can strategically remove a few taller branches to help make the plant more uniform at any time. By doing this, you’re only removing a few potential flowers because each flower bud is produced at the tip end of a branch. But if you shear or severely prune azaleas after July, you may severely reduce next spring’s flower production.
Here is a link for a UF/IFAS Extension publication on azaleas: https://edis.ifas.ufl.edu/publication/MG019.
Larry Williams is the Extension horticulture agent with the Okaloosa County Cooperative Extension Service, University of Florida. Contact Larry at 689-5850 or email firstname.lastname@example.org.