There really isn't going to be room for visitors in the Shed anyway.

With one significant exeption, I guess. Though, Charlie would hardly count as a visitor, would he?

Green as in spring green/apple green? Or leaf green, bottle green, moss green, British racing green? Blue as in lavender, indigo, azure, royal...? Soft pink, baby ping, cerise...? Need more detail. Is your icon a good palette to look at?