Tree · Sonoran native
Foothill Palo Verde
Parkinsonia microphylla · Fabaceae
Also called: Foothills Palo Verde, Yellow Palo Verde, Littleleaf Palo Verde
Foothill Palo Verde (Parkinsonia microphylla) is a very low-water tree native to the Sonoran Desert region well suited to Tucson and the low desert. It grows to 15-25 ft H x 15-20 ft W in full sun, with a slow growth rate.
Foothill Palo Verde at a glance
- Water use
- Very Low (established)
- Sun
- Full sun
- Mature size
- 15-25 ft H x 15-20 ft W
- Growth rate
- Slow
- Bloom
- Pale/creamy yellow (banner petal often white), Spring (April-May), about two weeks later than Blue Palo Verde.
- Cold hardiness
- Hardy to about 10-15 F; USDA zones 8-11.
- Soil
- Requires excellent drainage; thrives in poor, rocky, gravelly, alkaline desert soils and tolerates caliche. Does not need rich soil.
- Native range
- Sonoran Desert of Arizona and California into Sonora and Baja California, Mexico; characteristic of rocky desert slopes, bajadas, and foothills.
- Best used as
- Native/xeric landscape, Specimen tree, Wildlife and revegetation plantings, Slope and foothill plantings, Nurse plant for cacti
- Wildlife
- Classic nurse plant for young saguaros and other cacti; seeds are a key food for desert rodents, birds, and javelina; flowers feed native bees and other pollinators; provides cover and nesting sites.
- Toxicity
- Not considered toxic; seeds were a traditional food ground into meal.
How to grow Foothill Palo Verde in Tucson & the low desert
Watering
Extremely drought tolerant; established trees need little to no supplemental irrigation in Tucson and survive on rainfall. Occasional deep watering monthly in the hottest months speeds growth, but overwatering causes rank, weak growth.
Fertilizer & nutrients
No fertilizer needed; nitrogen-fixing legume. Fertilizing is unnecessary and can promote weak, floppy growth.
Pruning & care
Minimal pruning; remove dead wood and lightly shape after spring bloom. Slow growth means little pruning is required; avoid heavy cuts and topping.
Notes
One of the longest-lived and most abundant Sonoran Desert trees, living 100+ years. Slower-growing and more shrubby/multi-trunked than Blue Palo Verde, with tiny leaflets, yellow-green bark, and a thorn at each branch tip. More cold- and drought-hardy and a better choice for unirrigated native landscapes than the faster Blue Palo Verde.
Sources: University of Arizona Cooperative Extension; Arizona-Sonora Desert Museum; AMWUA Landscape Plants for the Arizona Desert; Tohono Chul