When asked to visualize a flowering tree, most of us probably would see some type of fruit tree like a plum or a pear. But the best flowering season is just upon us. The true desert dwellers are about to put on a spectacular display. Flowering is occuring later than average this season, perhaps this is an adaptation to avoid damage from late frosts and to take advantage of the highly active bee population.
Just take a look at the flowering trees along the airport connector along The Las Vegas Beltway to see what I mean. The palo verde trees are coming into their full glory right now, and they will continue to bloom for weeks. Although not native to Southern Nevada, these wonderful trees have become increasingly more popular. The first introduction to our area was the Jerusalem thorn tree (Parkinsonia aculeata). The green bark and long, compound leaves were an unusual oddity to local gardeners that were amazed by the profusion of yellow blossoms produced.
Then came other palo verde trees, including the blue (Parkinsonia florida) and the foothill (Parkinsonia microphylla). Both produce gorgeous displays of yellow flowers with the blue starting slightly earlier than the foothill. The next introduction was the hybrid of these three plants that bears the name Desert Museum. This fast-growing clone has no thorns and a larger and longer flower display.
If you are already tired of yellow, then let’s move on to white. April usually brings on the flowers of the orchid tree (Bauhinia lunarioides). This semievergreen tree is native to West Texas and Mexico, but it seems to be well adapted to our similar climate. The small leaves are two-lobed, and the delicate, five-petaled flowers have an orchid-like appearance.
The next white flowering tree to bloom is the Texas olive (Cordia boissieri). A native of southern Texas and northern Mexico, this small tree produces large, leathery leaves and clusters of funnel-shaped flowers. The fruit is olive-like in appearance, but that is the only resemblance. The flowers are insect-pollinated, so there are no concerns about pollen with this tree. It is slightly tender here, so it will not be evergreen like in its native habitat. However, it has proven to be a survivor once established.
When it gets really hot and seemingly every flowering tree has completed its cycle, then the desert willows (Chilopsis linearis) come into bloom. Native to our own Mojave Desert and throughout much of the Southwest, this small tree packs a mighty flower display. In the wild, you might see a wide variety of flower colors ranging from white to pale pink to deep lavender. This particular plant has received a lot of attention from nurseries and there are numerous selections to choose from with guaranteed flower color. There are deep burgundies, bi-colors with lavender and pink, and even seedless forms.
There are even plants from other continents considered late bloomers. The chaste tree (Vitex agnus-castus) also goes by the name monk’s pepper. Originating from Southern Europe and Asia, this plant has been used in the valley for decades, but is still not widely known. The palmately compound (hand-shaped leaves) are quite unique, but the spikes of deep lavender flowers are what we really appreciate. The long flower stalks borne on the branch tips are reminiscent of lilac flowers. It is said that the European monks would use the spicy seeds as a substitute for pepper when supplies of the real deal ran short. Producing a dazzling display during the late spring and into summer each of these plants, deserves more attention.
Dennis Swartzell is the marketing director for Mountain States Wholesale Nursery. As an ISA board-certified master arborist and a member of the American Society of Consulting Arborists, Swartzell has been helping Southern Nevadans with their gardening questions for over 20 years. If you have a question about a particular plant, or a general gardening issue, send them to Swartzell at email@example.com.