When to graft?

I have been reading a lot about grafting and thinking that at some point I want to try it. I am sure that there is an optimal time of year to graft. Obviously not in winter. When is the best time?

Here in SW Florida we graft from early spring once the plumeria start to show signs of life until late fall. Grafting in winter has little success.
The key is a good latex flow, which is only present when the plant is actively growing.

Good luck!

I second what Hetty said: http://davesgarden.com/community/forums/t/687551/