A group of local youths have found a shortcut through mine and a neighbours garden which has them climbing over a wall and standing on the roof of my shed. I am planning on building up the wall by a couple of block courses and bedding some terracotta planters on the top.
I am looking for some really nasty plants that are hardy enough to be out all year round with little maintainence.
Any horticulturists out there who can give me some ideas?
Sorry, but I don't want to hear any 'wait for them and batter them' ideas. The police know who they are and don't seem interested and they are the sort of idiots who wouldn't think twice about putting your windows through later.

