Tree of the Week: Palo Verde ‘Desert Museum’

This article was originally on a blog post platform and may be missing photos, graphics or links. See About archive blog posts.

Palo Verde ‘Desert Museum’ -- Cercidium ‘Desert Museum’

If it is desirable to plant an easy-on-the-water California native tree, what about the product of two or even three natives?

Palo Verde trees are tough, colorful, smaller-stature desert trees that get by on little; they are native to Southern California and beyond and have tiny leaves, bright yellow flowers and often mean thorns.

In the late 1970s, Mark Dimmit with the Arizona Sonora Desert Museum noticed how easily the local Palo Verde trees hybridized. They were the fast-growing Blue P.V., C. floridum, with bluish-green branches; the slow-growing Foothill or Littleleaf P.V., C. microphyllum, with yellowish green bark; and the Mexican P.V., C. aculeata (also called Parkinsonia), a vigorous upright grower. By 1981, Mark had found a robust seedling that combined all their best qualities: fast growth, bright flowers, upright appearance, light green bark and no thorns.

This semi-deciduous Palo Verde can grow to 20-plus feet tall and wide in five years. The canopy is an open and airy network of supple tiny twigs and small branches, casting a filtered shade. The tree looks best when pruning is limited to the essentials. Bark and twigs are smooth and light green. The feathered leaves carry multiple tiny leaflets. In spring, a cloud of yellow flower clusters covers the branches for weeks; sometimes intermittent repeat blooming occurs. Individual flowers are bright yellow, funnel-shaped, with brown stamens.

The tree produces few seeds and little litter. It will take a variety of soil and likes full sun. In our moderate non-desert Southland areas, it will benefit from a warm location; it may actually enjoy the reflected heat of a parking lot.

--Pieter Severynen

Thoughts? Comments?