We do not consider a garden dispute anti-social behaviour.
Sometimes neighbours disagree over the use of a shared garden, or dispute ownership of fences or walls.
Usually your tenancy will tell you what is and is not your responsibility, and normally states that boundaries should be kept in a good state of repair.
If you are sprucing up a boundary wall or fence it's a good idea to let your neighbours know first, and check that it won't cause them any problems.
If you are having a problem with your neighbour's use of an outdoor space, try having a chat with them to let them know or use a Dear Neighbour card [pdf] 469KB as they might not know that it is causing you an issue.