Pine needles: Pine needles are a trim-looking mulch for garden beds. They allow water to pass through easily and they break down slowly. Despite what you may have heard, using pine-needle mulch will not make your soil significantly more acid.
http://www.organicgardening.com/learn-and-grow/mulch
Oh! I had heard about the aciditity of pine mulch and had only used the mulch on my blue berries and strawberries as a result - found it to be great but was nervous to use it else where.