bird of paradise

5 year old plant that all of a sudden leaves are turning brown on ends and half of the leaves are turning yellow, help

Without more information, and some pictures, I can't help. Please post again, with pictures of exactly what's happening, and tell me where you are geographically, and where you have the plant, if in ground planted, or in a container, inside or out. Without knowing more about your situation, it's absolutely impossible to pin down what is wrong with your plant. Sorry to be so picky...