OK, the deat toll of my new garden is still very much under control with just one deceased aucuba out of 3. Fatsia has survived thanks to your kind advice but now... It looks to me as if I'm killing the new edge.
Well the edge is formed by 40 cm high Buxus sempervirens, most them arrived home green with the exception of one that had developed a yellow edge on the leaves. Now the other 29 seem to be joining in. They don't look dry (but they wouldn't even if I were about to kill them), I have checked the soild is compacted enough around the roots but the little things don't get any better.
Any ideas on where am I going wrong?