Dodgy privet hedge
 

I have a 20ft privet hedge on the east side of a garden wall. Three quarters of it has virtually stopped growing and the other quarter is growing like mad. The leaves on the dodgy section look very grey, altho the wood is still green.
Any suggestions gratefully accepted. It is not lack of water - I've checked the soil and it is moist.

Thanks for that - it's the exact opposite of what I'd been told locally. We have had a generally cool wet summer so far. I've cleared out around the roots and trimmed it so that there is a 6 inch space at the bottom, so fingers crossed.