Scientific: Leucophyllum candidum (varieties silver
cloudTM and variety thunder cloudTM)
Common: Silver leaf sage, violet silver leaf sage
Family: Scrophulariaceae
Origin: Chihuahuan desert from Brewster county in Texas south into western Coahuila, extreme eastern Chihuahua,
northern Durango, and northern Zacatecas.
Pronounciation: Lou-co-FIL-lum can-DEE-dum
Hardiness zones:
Sunset 7-24
USDA 8-11 (arid and semi arid zones only)
Landscape Use: Accent, informal hedge, filler for desert gardens and landscape settings, rock gardens, useful where gray color and a fine texture is desired.
Form & Character: Rounded and compact to irregular, dry and open in appearance, recessive.
Growth Habit: Evergreen, woody, broadleaf perennial shrub. The variety silver cloud grows moderately to 4- to 5-feet tall, whilst variety thunder cloud grows more slowly to 3- to 4-feet tall. Both varieties have spreads that are about equal to their height.
Foliage/Texture: Leaves are alternately arranged on the stem, silver gray (nearly white), highly tomentose foliage and stems, leaves small to 1-inch long or less, elliptic to obovate and sessile; fine texture.
Flowers & Fruits: Profuse small axillary indigo-colored flowers, fruits are inconspicuous. All Leucophyllum taxa produce reproductive growth (flowers and fruits) on new wood.
Seasonal Color: Flowers during warm season, peak flowering in late summer to early fall.
Temperature: Very tolerant of Phoenix heat and cold.
Light: Full sun, shade intolerant.
Soil: Prefers alkaline soils and MUST have a well-drained soil.
Special Note: Of all the Leucophyllum species, candidum is most prone to root rot if soil drainage is poor.
Watering: Apply no supplemental water during winter! Add supplemental water during summer particularly if monsoon rains are paltry.
Pruning: Best if pruned (only lightly and sparingly) once a year in late February to mid March. In fact, the variety thunder cloudTM may not need pruning at all due to its diminutive stature. And as always with all Leucophyllum species, PLEASE DO NOT SHEAR!!!
Propagation: Seed and cutting
Disease and Pests: Texas root rot in poorly drained formerly agricultural soils is common.
Additional comments: Silver leaf sage leaves are more persistent in winter and smaller than Leucophyllum frutescens. Variety thunder cloud (introduced by the Texas Agricultural Experiment Station in 1985) is a smaller, superior improved version of var. silver cloud (introduced by the Texas Agricultural Experiment Station in Dallas in 1983) and is less prone to shearing abuse by landscape hacks and wannabies (aka 'Hort clods') with their lite beer (in cans which they throw onto the side of the road) and their Lithium battery powered shears and gas powered blowers.
