We have recently moved to a new house - with a new garden. Part of the fence has blown over in the strong winds and needs to be replaced.
There are three tall (2.5m) Cornus alba (possibly Sibirica) encroaching on the fence and it would be good if these could be pruned before the fence is done. Would there be negative consequences if I pruned them back hard now already? (RHS suggests Feb/March for pruning.)
Have I understood correctly that I should just cut all the stems down to 5-7cm from the ground?
You can prune them now. If they are encroaching on the fence, I would prune them and then dig them up divide them. Plant them a little further away from the fence. Cornus are easy plants to move, I stick my pruningS In the ground and get lots of new plants that way.
I think what would probably happen is new growth from the roots. I did mine in 2 stages, half then the rest out . The original looks like yours but I now have some new tall red stems that grew last year. Hopefully someone who knows for sure will be along.