If these are treated you may have to wait six months. Your choice of stain will range from semi-transparent to solid. Stains are available in both water based and oil based products depending on where you are. I used to be a purist and only use oil-based for penetrating stains but the waterbased products rival them now I think.
You can get quality penetrating semi-transparent stains (Cabot and Sickkens come to mind) at your paint store, not your box store, in a variety of colors including cedar. How the color will actually look when it hits the spruce may vary from the color chart though so try a small container on a test area first.
Solid color acrylic stains (Sherwin Williams Woodscapes would be my choice) can be tinted to any color just like paint. They allow you to retain the texture of the wood grain but cover it completely with flat color. They do not require a primer.
Last edited by user1007; 07-24-2012 at 06:14 PM.
Reason: Added Photos