If you really want success in your garden try growing plants that are supposed to grow here.
Check out www.nativeseeds.org. This is an non-profit organization, based in Tucson, that sells seeds of crops traditionally grown in the American Southwest and Mexico, as well as crafts, gift baskets, and notecards.
This year my wife planted a delicious bunching onion from their site. She has also successfully grown sorghum and devil's claw that she had ordered from them.