Pruning Box hedge

I just snip off the long new growth back to a height that I'm happy with.

I have some growing as a low hedge that gets trimmed back to the same height twice a year.

I also have several topiary shapes I am playing with, these also get trimmed at least twice a year.

A good tip though, if they are in a pot, sit the pot on an old blanket/sheet as the clippings go everywhere.

Try to avoid doing it in the mid day sun or any dry hot periods. leave it till evenings, when suns decending, or early early mornings before the heat of the sun bears down!
This helps to lower the risk of the leaves gettting scorched and you having brown edges on them. Also once cut i tend to hose down the hedge too

Box prefers being clipped on a dull day, and May is usually a good time. Which reminds me, I've not done mine this year and the shape has gone from the knot, which looks very blurred and untidy.

I use electric hedge trimmers! Ouch...but an awful lot easier on the back and knees!

Topiay shears are good too, basically like sheep shearing shears!

Some say that you should prune box on Derby Day.

Thanks for your comments everyone, were most helpful