Scientific: Brahea armata (Synonym: Erythea armata, E. glauca, E. roezlii)
Common: Mexican blue fan palm, blue hesper palm
Family: Arecaceae
Origin: Native to rocky canyons of Baja California and Sonora, Mexico.

Pronounciation: Bra-HEE-a are-MA-ta

Hardiness zones
Sunset
12-17, 19-24
USDA 8 (with cold protection), 9-11 (arid and semi arid region best)

Landscape Use: Accent palm, residential and commercial plantings, a versatile palm for textural and color accents in mesic, oasis and xeric landscape design themes located in arid and semiarid climates. B. armata will not grow in humid subtropical or tropical climates like Florida. It likes it dry!

Form & Character: Classy, single-trunk palm with an elephant hide like, semi-self shedding trunk. It is similar to a small W. filifera in stature (except for the color of the fronds). A reserved and dignified palm.

Growth Habit: This is a VERY slow growing palm, especially when young, but eventually will reach 30 or more feet in height. At 15 years from seed, it will only be about 5 to 8 feet tall.

Foliage/texture: Large fronds are costapalmate (possessing a longitudinal rib), glaucous blue gray and partially subdivided into as many as 20 to 40 pinnae. Petioles are only slightly armed (dark thorns) and extend inlength to more than half of the central leaf blade. Fronds on mature specimens can spread in width to 5 to 9 feet; coarse textured.

Flowers & fruits: Long, arching stalks containing plumes of cream-colored flowers followed later by conspicuous, golden yellow fading to black non-edible fruits. The plumes of flowers and fruit easily twice exceed the width of foliar canopy. Ripen fruits though tough and nutty are edible, but why?

Seasonal color: Cream flower plumes and golden braids of fruits in early summer, grayish-blue foliage all year; what a palm!!

Temperature: Cold hardy to 15oF enabling inland and more northern landscape use into USDA zone 8. More cold hardy than W. filifera even though it is found naturally farther to the south.

Light: Full sun

Soil: Needs good soil drainage and might sometimes need supplemental magnesium fertilizer in areas with excessively alkaline soil. In the Phoenix area, grows fastest in former agricultural soils.

Watering: In desert locations, generally irrigate infrequently with a tendency to apply more water during the hot summer months.

Pruning: None, except to remove old or dead fronds. This palm is very slow to recover from severe scalping, so don't prune Mexican blue fan palm as if it were a Washingtonia sp.

Propagation: Seed, slow to germinate sometimes taking 1 to 4 months. Presoak fresh seed in warm water for 24 hours appears to slightly hasten germination time. I germinate Brahea seeds (several species) in closed baggies filled with moisten peat moss drenched first with the fungicide Captan. Keep warm (70-85oF) and out of direct light. After germination transplant seedlings immediately. I recommend direct potting into 5-gallon containers as they produce a very long tap root.

Disease and pests: None

Additional comments: Wow!! Brahea is a great genus. Blue hesper palm is a relatively small and glaucous substitute for W. filifera and is a great palm for landscapes in southern California and Arizona. Note this bodacious specimen in downtown LA! Transplants easily - transplant larger boxed or container specimens because of its slow growth rate.

Note: Recent biomedical research has shown that fractions of the aqueous alcohol extracts of the rind and kernel of Brahea aramata fruits suppress activity of 5-alpha-reductase type II, which is expressed predominantly in the prostate and could be a major target for drugs against benign prostate hyperplasia (BPH) and prostate cancer (Pharmazie. 2006. Volume 12:1034-1037).