One of the best passive solar methods I have seen is to use plants and trees to obstruct the Southern view of the sun. As fall approaches, the leaves fall off

One of the best passive solar methods I have seen is to use plants and trees to obstruct the Southern view of the sun. As fall approaches, the leaves fall off of the trees, allowing sunlight to pass, and warm your home. As spring approaches, the leaves return, blocking the sun, and keeping your house cool. ALSO, a green roof would be awesome AND a "natural pool".