Pronounciation: LAR-ree-a tri-den-TA-ta

Hardiness zones
Sunset 10-13, 19
USDA 8-11 (in arid regions only)

Landscape Use: Xeriscape accent, background, foundation, rock gardens, habitat restoration.

Form & Character: Straggly, open, upright, and sparse in dry soil, more dense and spreading when planted in irrigated sites, though will become excessively tall and ragged with age in urban landscapes if left unpruned.

Growth Habit: Mostly evergreen to drought-deciduous perennial shrub, slow to moderate growth ranging from 3 to 15 feet tall, mostly 3 to 8 feet. The growth rate is greatly increased if creosote bush is able to access a consistent source of soil water.

Foliage/Texture: Small to 1/2 inch, leaves divided into two crescents (bifoliate), viscid, strongly aromatic when wet (the smell of the desert), stems ringed with corky residue of former leaf stipules; fine texture.

Flowers & Fruits: Small yellow flowers followed by rounded fruit covered with white hairs that facilitate wind dispersal.

Seasonal Color: Yellow flowers in spring, occasional sporadic blooms in fall after summer monsoon rains.

Temperature: Tolerant

Light: Full sun, no shade of any amount.

Soil: Tolerant, but well drained.

Watering: Creosote bush grows rapidly and becomes very large and gangly if given supplemental irrigation....so don't! Its use in the landscape in a sustainable fashion means to NOT water it. Though one may want to give it a "big drink of water" on rare occassions, it will grow slower and will ultimately maintain a more compact dense shape if not regularly irrigated.

Pruning: Trained horticulturists will lightly head back creosote bush to encourage a more rounded, yet still natural looking habit of growth. Creosote bush can also be rarely severely pruned to near ground level to rejuvenate vigor. More traditional 'red neck' (two bit haircuts for all) horticulturists, locally called 'hort clods, will frequently shear creosote bush so as to make it look like and conform to the quintessential Phoenix 'beer keg' plant form. And you know what, creosote bush actually looks mod with a que ball look.

Propagation: Seed, cutting.

Disease and Pests: Creosote gall, no recommended control measures.

Additional comments: Creosote bush is a desert plant of legend: the desert smells like creosote bush after most rains. Allopathic oils from creosote bush leach into surrounding soils and inhibit mitochondrial oxidation of embryo sugars inhibiting seed germination of other plants. Within the Sonoran and Mojave desert flats, native desert stands called "creosote flats" contain single creosote plants may reach one thousand years old or older by forming large rings of seemingly many plants.

Bioindustrial uses: The biochemical properties of oils derived from creosote bush are used for a range of industrial and health applications.

Taxonomic tidbit:The genus name Larrea comes from the Spanish clergyman, Bishop Juan Antonio Hernandez Perez de Larrea (1731-1803).