Box Tree Clipping
Box tree clipping around Derby Day is commonly regarded as the right time to prune box trees and bushes.
The timing of box tree clipping and box hedge trimming comes from way back when the family at the big house decamped to Epsom for the Derby.
The Derby horse racing festival is at the start of June. You see, trimming vast amounts of box plants was messy, required unsightly equipment and generally spoils the view! So what better time to do it than when the house was empty.
It just so happens that early June is in fact a good time for box tree clipping as the risk of late frost has diminished. I find that the new growth on box [Buxus sempervirens] can be surprisingly frost prone. It can also bleach in strong sun when new growth is removed exposing shaded shoots below.
Box Tree Problems
There are now a couple of serious threats to the health of box trees. Whilst one is as yet over the horizon for most West Country gardeners [box tree moth], the other [box blight] is already here in our neck of the woods. Both are recently introduced to the UK and if left unchecked are devastating for box trees!
I’m afraid that control methods for both are limited. I suggest that it is essential to monitor your plants regularly for this pest and disease. So I believe that there is no better time to do that than when you are up close and personal with a pair of garden shears?
You might see similar symptoms on your box for both ailments. Do look for patches of dead leaves and sections of hedges that are dying back.
Box Tree Moth
The moth caterpillars – usually hidden within webbing- will confirm the box tree moth’s presence in your area. It’s already widespread in London! Pheromone traps can be hung to monitor for moths in the vicinity. If caught early enough, picking caterpillars off maybe enough but try also control with nematodes suitable for caterpillars. Insecticides will need to be thoroughly and forcefully applied to penetrate the webbing.
But back to box tree clipping; there is a consideration in how you do this to minimise the risk of box blight infection and spread. Do avoid overly crowded growth. Allow as much air circulation around plants as possible. Move away with those perennial plants leaning against the neatly clipped hedge! Pick up and compost as many trimmings as you can. Give your box bush a good shake to clear out dead leaf matter lodging inside. I also recommend that you make a habit of dipping your sharp shears into a bucket of water and mild sterilant. These measures minimise the likelihood of your trees becoming infected.
Alternatives to box
I can recommend some alternatives to those neat and formal box trees that we have loved and grown for centuries?
Here are a few that I think come pretty close to box.
The small-leaf Japanese holly Ilex crenata is my front runner.
But I suggest that you could try Lonicera pileata which is much faster growing.
At Highgrove Royal Gardens I’ve seen that diseased box has been replaced by bee friendly Teucrium x lucidrys.
I think that some of the small leaf Hebe work and I’d suggest Hebe rakaiensis, subalpina or topiaria.
Perhaps you too have boxed clever and had success with other species. If so I’d like to hear from you!
I’ve written about other pruning here –