I am right on the border between Zones 5 & 6 and wondered if anyone knows when and how I should prune my limelight hydrangeas. I have read late fall-early spring but is it now early spring or is this a bit early in zones 5-6.
I understand they grow on new growth so should I prune them to the ground.
Sorry for the questions--they were beautiful last summer and I have neighbors planting them now too so I know they will be asking too.
Connie
Limelight Pruning in Zone 5-6
Since they bloom on new growth it doesn't matter as much when you prune them, fall or spring are both fine. It's the H.macrophyllas that bloom on old wood where you need to be careful on the pruning time. There's no reason to prune it all the way to the ground though unless it's gotten really overgrown, and even then I'm not sure if this is one of those plants that responds well to that sort of pruning or not--some shrubs won't come back if you prune them all the way to the ground so I'd make sure you get some good info on whether this one will come back or not before you do anything that drastic (I honestly don't know what would happen with Limelight...all I know is that some shrubs respond well to being cut to the ground, but others won't come back so you need to make sure and know what's right for your shrub!). If it's got a good shape and you like the size it is and want it to get bigger, you wouldn't necessarily have to prune it at all, but if you're trying to control size or if it's getting a lot of branches really crowded in the middle then it certainly won't hurt to do some pruning.
Limelight will come back if pruned to the ground, but I see no sense in doing so. I just prune off last years flowers in the early spring. Since it flowers so heavily, that's about all the pruning it needs to make a nice shape.
Making a nice shape is all you need to do with Limelight, unless training it to a tree form.
You can do this now, or wait awhile. I wouldn't prune it after April in Z6.
I prune my Limelights and other paniculatas in spring once they start to bud out. Always a little dieback and old flowers to prune out then. These aren't the kind you cut down to the ground.