Leylandi (yellow conifer hedge)

Have you trimmed it too hard into the dead wood? Unfortunately, all you can do is let the growth nearest to each die-back area grow a bit long and then try to tie in the new shoots and 'disguise ' the brown areas. I've seen this done with reasonable success. The only other drastic thing you can do is to take out the ones that have this problem and replace them, but your hedge won't look right for some years, of course.

Thank you for helpful information. I am told by our local Garden Centre that there is a virus affecting Leylandi this summer and looks the same as you described by cutting too far back and it almost looks scorched. So I am not sure which I have. The product recommended is called Provado. This is a systemic spray which will halt the browning but will probably not grow back. Your suggestion regarding the new shoots is probably the way to go.

Many thanks.