STAFF PICK: You might head out to Green Things nursery on a scorching Tucson Saturday to pick up a lush Tahitian Bridal Veil plant for a hostess gift. In the endless dry heat of June, you might simply want to spend a bit of your afternoon enjoying the temperate humidity of the enormous greenhouse. When you emerge all misty and revived, ready for the drive back home, you think you notice a dromedary. And another. You are certain that you are facing a field of camels, but think it's not possible. Think again. Green Things is, we can safely say, the only nursery in Tucson that provides a Middle Eastern ambience.