Actually, to defend my professional reputation, I am very good at keeping topiary to the shape, size and proportion that is intended: these particular box balls belong to a garden which I only attend at irregular intervals, and they didn't always have as many clips as they should have!
Last week, the Client asked me to give them a good chop, as they were now so close together that he couldn't get the wheelbarrow through without scraping his knuckles, which was getting annoying.
So I set to work to give them a once-every-few-years Major Chop.
Warning: this is not for the faint-hearted!
It is clearly time for some attention and there are two main options: either you can dig them out and replace them with small ones, or you can give them a drastic chop - the plants are Box, Buxus sempervirens, which regrows well, when cut back.
So, what am I going to do? Instead of doing the normal trim which involves clipping off the new soft growth of an inch or two, I am going to cut off at least six inches (15cms), using secateurs instead of shears.
If the thought of doing this makes you faint with horror, I suggest you look inside one of these clipped box topiaries some time: if you gently part the outside foliage, you will see that right down inside, where it is permanently dark and gloomy, there is a surprising amount of fresh new growth, in small sprouts. This tells you that the plant is one of those that will "come back" from a hard chop. Others include most Hebe, and Choisya, but most definitely do not include most conifer hedging!
My method is to simply part the foliage, insert one hand with the secateurs, go back as far as I think necessary, and simply start cutting. If the topiary is in fairly good shape apart from being too large, then if you take off the same amount each time, you will find that you retain the shape almost perfectly.
I find this does not work well with mechanical hedge-trimmers:; they can't cope with the thicker inner stems, and it is not easy to keep cutting a consistent depth inside the original outline. It might take a little longer by hand, but it's a lot more accurate, as well as being more peaceful for everyone around.
You can see from the cut edge how I am taking off quite literally six inches, and am keeping the original shape.
Looks fairly bald and scary, doesn't it?!
All that remains now is a little final tweaking of the shape, which I find is best done after clearing away the mess, so that you can more easily assess the shape, proportion and balance of the two plants.
Then they will get a fistful of balanced fertiliser such as Growmore, and maybe some pelleted chicken manure, and a good watering. This should get them off to a good start on "greening up".
So there you have it - how to Be Bold with overgrown Box topiary.