I have a waspinator hanging in my plum tree. I got it last year from Wilkinsons, I think it was £7.99. Basically, it is a round, grey, material bag which is supposed to mimic a wasps nest. If you hang where the wasps are, they are supposed to be fooled into thinking that another bunch of wasps are already nesting in that particular spot, so they go away and look somewhere else. I had good success with it last year, I hung it up nice and early and we did not seem to have very many wasps on the fruit at all.