How to use a different material on each side of leaves (or texture map them)?

I need to make a snow forest. Leaves will have snow on the top side and green on the bottom side, when I create a texture that has both elements (white and green), unity won’t apply half to each side. Also if I have 2 different textures, I can’t apply either. I tried both with billboard and plane geometry.
Could you guys point me a good way to tackle this?

I don’t think this is a Unity Issue, I believe you have to make sure the model is UV unwrapped in a modeling program. I’m not an artist but I cheat and use Blender then separate the two sides by material, then I smart UV project to the model.