I can see why it would be an obsession. Colors are always an awesome thing to photograph. It isnt always clear how to compose them though. Maybe if you step back and then get closer with the lens. Make sure the fence completely fills the frame, and put one of the fence posts on one of the thirds. The color, texture and lines of the fence would make a picture full of color and texture. Its not always about what is around the obejct, keeping the object completely isolated works wonders.