How to stop kittens climbing trees

[image error] For those who have been following the story of our three foster kittens, they are thriving... They get naughtier every day, climb our grapevine and are generally a nuisance. (Try sweeping the patio with three kittens hanging on the broom!) 

Climbing the grapevine may not seem a serious issue, but it is. The vine means access to the rooftops, and that way, into the village. The village is full of dogs, and now that it's summer, children. Joe and I are afraid that the kittens will get lost, or ...