Blue hesper palm at Miami's Fairchild Tropical Garden.
Distinctive, unique and attractive, the blue hesper palm has a crown of rigid leaves which radiate from the trunk top. Blue hesper palms are considered by many to have the bluest leaves of any palm in the world. The leaves of a hesper palm may also be pastel bluish white or aquamarine in color. Blue hesper palm may grow 50 ft (15.2 m) tall and 16 ft (4.9 m) in width. The blue hesper palm trunk is slightly swollen at the base and grows up to 1.5 ft (0.5 m) in diameter. It usually has persistent scars from the bases of petioles (leaf stems) that have since dropped off or been removed. Blue hesper palm may have up to 30 palmate, or fan shaped, circular leaves. If old leaves are not removed, they form a continuous brown skirt, reaching from the top of the trunk all the way to the ground. On the top side of the base of the leaves, where they join the stem, there is a thin "flap." The petiole of the blue hesper palm is armed along the margins with curved thorns, many of which branch into two points. Blue hesper palm produces multiple branching inflorescences up to 3 ft (0.9 m) long, which project out and often downward from the leaf crown. The flower cluster consists of many small whitish bisexual blossoms and is considered by many to be among the most beautiful of palm flowers. The shiny fruit of the blue hesper palm is round and brownish black, about 3/4 in (1.9 cm) in diameter, and contains a single seed.
Blue hesper palm grows naturally in desert canyons and cliffs on rocky limestone soils in northwestern Mexico (Baja California and Sonora) at low to medium altitudes.
Blue hesper palm succeeds admirably in a wide range of soils in subtropical climates. Blue hesper palm can grow in limestone alkaline soils and is fairly tolerant of salty soils. These are true desert palms and, once established, can withstand intense heat, drought and considerable frost. Traditionally considered a slow growing palm, the blue hesper palm responds very well to moist, not wet, soils and fertilization. A slow release fertilizer with minor elements (e.g., an 18-18-18) may be used to enhance growth. Blue hesper palms may bloom at exceptionally early ages and young palms have very large, distinctive and colorful leaves. When transplanting a blue hesper palm, it is prudent to exercise care to minimize damage to the root structure or individual roots. Some experts recommend simply planting the whole pot to avoid disturbing the sensitive roots, and to minimize transplant shock. Eventually the transplanted palm sends roots out of the cracks in the pot and continues to grow. Two reports from palm experts indicate that significantly damaged blue hesper palm roots may be slow to heal and this slow healing may initially and adversely affect the plant's health and ultimate size. Some experts also say that sealing root ends which get damaged in the transplant process will significantly ease transplant shock. Light: Blue hesper palm prefers exposure to full sunlight, but also grows well in part sun/shade. Potted blue hesper palms require a lot of light. Moisture: Soils should be moist with good drainage for optimal growth. Blue hester can tolerate drought. Hardiness: USDA Zones 8 - 11. The adult blue hesper palm can withstand extreme heat and can withstand frost and freezes. Reports of cold hardiness for established blue hesper palms indicate the tree withstands 17ºF (-8.3ºC) with no damage to foliage and withstands 10ºF (-12.2ºC) with only minor foliage damage. Planting the blue hesper palm in fast draining soil enhances cold hardiness. A cold hardiness rule-of-thumb for the blue hesper palm is: if you can grow a California fan palm (Washingtonia filifera) in your area, the climate should also be appropriate for the blue hesper palm. Propagation: Blue hesper palm is easily propagated from seed. Seeds are considered to have maximum viability if sown within 8-16 weeks after maturing. However, some blue hesper palm seeds are reported to germinate very easily, even after three years. Germination of fresh seed usually takes place in 3-4 months. Application of heat to the bottom of the germination trays or pots has proven to improve germination rates.
This is a fine palm for garden, yard, street, avenue and parkland planting. Plant outdoors in a site that can accommodate the large head of leaves and 50 ft (15.2 m) height that the blue hesper palm may grow to. Young blue hesper palms do very well in pots or tubs in sunny or well-lit areas.
Blue hesper palm is a beautiful palm whose color can be so blue that it is arresting! This distinctive palm makes an extraordinary accent plant. Blue hesper palm usually becomes a focal point with its large fan shaped leaves and distinctive coloration. The inflorescence of the blue hesper palm is considered by many to be one of the most beautiful among all the palms. The blue hesper palm is easy to grow and resistant to freezing. The genus name honors the Danish Astronomer, Tycho Brahe (1546 - 1601). The species part of the name comes from the Latin word meaning "armed."
The petioles of blue hesper palms are heavily armed. This palm is best planted away from foot paths or walkways. Also, it is advised not to plant the blue hesper palm under power lines or other overhead structures as it will eventually reach 50 ft (15.2 m) in height.