Rhododendron cutting back help

[David A]

We have a lot of rhododendrons and around the drive the previous house owners didn’t keep hugely on top of them so they are protruding probably about a foot too far into the driveway.

I’d like to trim them back a good amount eg 12-18” but don’t want to lose the foliage long term and want them to get a bit more height too.

Possible? Prune in one go? Now / spring / summer ?

[LeadFarmer]

You will probably find that there are flowering buds on there ready to open up next spring, pruning now would mean no flowers next year.

December isn't a good time to prune as you are opening up the cuts to the freezing weather.

Either cut it back next spring (and lose flowers for 2019) or wait until its flowered, then cut it back.

[Candellara]

David A said:

We have a lot of rhododendrons and around the drive the previous house owners didn’t keep hugely on top of them so they are protruding probably about a foot too far into the driveway.

I’d like to trim them back a good amount eg 12-18” but don’t want to lose the foliage long term and want them to get a bit more height too.

Possible? Prune in one go? Now / spring / summer ?

Had the same issue. I decided to prune them right back. I was pretty much left with nothing as I pruned them a bit too heavily :-) 12 months later they are better than they have ever been. Don't be scared to be quite aggressive. It'll take one season to get the foliage back but I think it did them the world of good as they now have a really nice shape and the foliage is dense and a lot greener than ever

[CharlesdeGaulle]

LeadFarmer said:

...wait until its flowered, then cut it back.

This is what I would do, but they are tough and resilient and seem to come back after anything.

At a previous house, I had the gardener (yeah, yeah, I know...) cut them back savagely to un-do years of neglect and over-growth, and within 18 months or so they were better then ever. They really do need to be controlled in my view to be at their best.

[Andrew_S]

You really should wait until the last spring frost before pruning them. They won’t like it before then.

[Skyedriver]

LeadFarmer said:

You will probably find that there are flowering buds on there ready to open up next spring, pruning now would mean no flowers next year.

December isn't a good time to prune as you are opening up the cuts to the freezing weather.

Either cut it back next spring (and lose flowers for 2019) or wait until its flowered, then cut it back.

^^ THIS^^

I lived on the Isle of Skye for a number of years and the R Ponticum was considered a weed by some and there was actually a programme of removing them. Didn't work (fortunately).
I had a number around our garden and used to cut them back AFTER the flowering. Meant you got the flower and there was enough time for them to recover and regrow enough to flower again next year, but yes you can cut them right back and they won't come to any harm.

[David A]

OK, consensus seems to be - after flowering, hack back.

I may report back with pictures at somepoint.

Thanks all.

[NDA]

As others have said, cut back in the spring.

You can be fairly brutal, but cut back to a bud (not including the bud) where possible and be prepared for one season of lost or thinner foliage. It will probably come back thicker than before - once established, Rhododendron's are very hardy.