Cactus plants probably grew in tropical environments until about 65 million years ago when, in much of California, the climate changed from year-round rainfall to a pattern of dry summers and wet winters. Later, when deserts began to form as the Sierra Nevada and Peninsular Ranges rose and blocked rainfall into the eastern valleys, cacti adapted to dry desert conditions. The development of ornamental plants for decorating the house is becoming popular today. Now, house decorating is not only don