The cuticle is a waxy layer made up of cutin which covers the surface of the leaves, reducing water loss. This si usually thicker in drought-tolerant plants. Leaves and stems may sometimes be covered with microscopic hairs called trichomes which shade the plant while at the same time reducing wind velocity. This protective covering of hair is called pubescence and appears grey to the naked eye. Many plants will fold or roll up their leaves in items of drought, again reducing the surface area from which water can evaporate.
Saxifrage are an example.
Plants which are extremely succulent with thick, waxy leaves have an extra capacity for storing water which they can use in times of drought - the camel's hump of the plant world. Hens and chicks and sedum are examples of drought survival through succulence. Xerophytic plants are those plants which are so adapted as to survive on natural precipitation or with minimal irrigation. In Saskatchewan, the average annual precipitation is 33 centimeters. For specific plant material recommended for the concept of xeriscape see the Manual of Drought Tolerant Plant Material.