Caching for a method in application helper

Hello All,
I have a partial which is rendering on all pages of my web site. Which
is using a method from application helper to get datas. Because of
this partial loading in all pages making my site slow.Any one have a
good idea of how to do caching for the method inside the application
helper. Basically this method getting me three object arrays using find
(:all) and using that I have to build a tree.

Thanks in advance