Desert plant adaptations
When we speak about deserts and the things that can actually survive there, it is hard to imagine just how plants are able to do it! A few days that included gale force winds, followed by torrential downpours, and temperatures that bounced from the 50’s at night to well over 80°F during the day would definitely have been stressful.
Our common garden plants are able to thrive in large part because of the amounts of time, energy and resources that we are willing to donate to them. Since so many of them originated in very different environments from the Mojave, that is the only way they can grow well here. We get so much from our introductions; shade from tall, leafy trees, fruit from shorter ones, and masses of blossoms in any season that we choose.
Desert plants, at least those that are not growing around our homes, generally do not have anyone around who will protect them from the elements. Still, they have managed to endure and evolve characteristics that make them perfect for life in a harsh world.
While the desert does not have much in the line of tall shade trees, there are native trees here. The beautiful flowering desert willow is now in full bloom, for instance. The flowers appear as mini-orchids, pale pink, lavender and white blossoms. This gorgeous tree can be a terrific landscape plant. Given water and decent soil, it will grow better than 15 feet tall. It sheds its leaves in the winter, just like any other deciduous one. The leaves are slender, although not so narrow as one might expect in a Mojave native. It is not much of a shade tree, but it will filter light and provide a lovely screen. In the wild, when there are no people to coddle it, it will not grow so high or be quite so rich looking, but it will certainly survive.
Mesquite and acacia leaves are considerably smaller than those of the desert willow. These durable plants live when other trees will certainly succumb to heat and drought. Their tiny leaves do not lose much water, and their roots are able to grow far down into the soil, following moisture as deep as 80 feet. Contrary to some opinion, roots do not “mine” for water; they cannot grow in dry soil. They do make the most of whatever little amount there may be, however. Again, we would not plant them for their shade, but visually, they are amazing, and do have interesting flowers.
Adaptations keep plants alive through the extremes of the desert. Small leaves are often fuzzy. This fuzz protects the tender green tissue from sunscald, and acts as a baffle to slow water transpiration. Yuccas and agaves have tough leaves with a waxy layer to reduce water loss. Agave leaves also tend to be quite thick with stored water.
The differences among various desert plants, such as leaf size, shape and even the angle of their leaves are all ways for them to survive in a hostile world. They deserve our admiration.
Email or call Angela O’Callaghan, Social Horticulture Specialist for University of Nevada Cooperative Extension, at 702-257-5581.