Organic matter high in carbon — what composters commonly call browns — provides energy for decomposer organisms as they consume and break down the contents of your compost pile. Organic matter high in nitrogen — called greens — supplies the decomposers with protein. Maintain well-fed composting organisms with these varied ingredients.

BrownsGreens
Dry leaves Kitchen scraps
Woody plant trimmings Coffee grounds and filters
Straw Leafy plant trimmings
Pine needles Grass clippings
Sawdust Manure
Paper products Feathers, fur, and hair