By Jan65
North East England,
United Kingdom 
Hi there - my first question for quite some time! My dad who has just moved house has a largeish pyracantha hedge at the bottom of the garden. The height, at about 7 foot, is not a problem, but the depth of it is. I think it's probably about 4-5 foot deep. He wants to keep it for security reasons (their garden backs onto a public footpath) but would like to reduce the width, probably by about half. If he does this, will the shrub green up again or will he be left just with a lot of wood and maybe even lose the shrub all together? Many thanks for any advice.
3 Mar, 2011
Answers
Hi,
Time to do it is now, before growing season really begins. Use strong gloves.
You should prune both sides of your hedge-suggest pruning the public side of hedge first, because of your responsibility to keep a prickly hedge like this in good keep.
Weave any bendable branches into the hedge to keep the mass but reduce the width of the hedge.
If you trim the garden part most but not too much (say over 1/3 of the overall hedge mass this year) then it will look a lot tidier and will regrow. If you keep pruning it over the next few years it will keep regrowing and green but maintain a smaller size on the garden side.
3 Mar, 2011
Hi Bloomer and Kildermorie, thank you very much for your replies, much appreciated.
Luckily the public side of the hedge is restricted as it is covered by a fence - hence it's only grown one way, into the garden!
So if I've understood you correctly, dad can cut it back by about a third this year, and it should green up and recover.
And can he do the same next year and so on until he gets it to the width he wants it?
3 Mar, 2011
Save some of the prunings to place over seed beds to keep the cats off!
3 Mar, 2011
Hi Jan,
Yip 1/3 of its current mass this year then no more than 1/3 of the hedge mass that it is next year. It does regrow well, but do not go over 1/3 as the hedge may not recover from such a haircut.
4 Mar, 2011
Thank you Volunteer (great tip!) and Kildermorie, I will pass on this information to my dad. Thanks again.
5 Mar, 2011
Hi Jan,I have one which is wide too,but not as wide as your dad's.I do trim it back,as it encroaches on other plants.I would cut it back to where you can see new growth appearing,as maybe if it is woody,it might not re generate..Not certain for sure though,but someone else will know,if that could happen.Hope this helps..
3 Mar, 2011