Washingtonia filifera
California fan palm
Overview
Washingtonia filifera is a single-trunked fan palm reaching 40-60 feet (12-18 m) tall with a stout, gray, columnar trunk up to 3 feet (90 cm) in diameter. The fan-shaped leaves span 3-6 feet (0.9-1.8 m) across on spined petioles 3-5 feet (0.9-1.5 m) long, and the segments carry curling white thread-like fibers along their edges that give the species its name. Old fronds bend down and persist against the trunk, forming a dense brown skirt unless removed. Branched flower clusters extend 8-15 feet (2.4-4.5 m) beyond the leaves in early summer, bearing many small cream flowers followed by pea-sized black fruits about 0.4 inch (10 mm) long. The trunk thickens with age and shows old leaf-base scars near the crown. It grows naturally around desert springs and seeps and tolerates heat, alkaline soil, and brief flooding. The persistent leaf skirt is a fire hazard in dry settings and serves as nesting cover for rodents. Growth is moderate, adding 1-3 feet (30-90 cm) of height a year in warm climates with regular water.
Native Range
Washingtonia filifera is native to the desert Southwest of North America, growing around springs, streams, and canyon seeps in southern California, western Arizona, and the Baja California peninsula of Mexico. It occurs in scattered oasis stands within the Sonoran and Mojave deserts below 3,500 feet (1,070 m).Suggested Uses
Planted as a specimen and street palm in desert and Mediterranean climates, and in large parks and avenues where its height suits the scale. It is grown around pools and in arid landscapes for vertical structure. The fruit and flowers draw birds and bees.How to Identify
Appearance
Size & Dimensions
Height40' - 60'
Width/Spread10' - 15'
Reaches mature size in approximately 25 years
Colors
Bloom Information
Long branched flower stalks emerge in late spring to early summer, generally May to June, arching well beyond the foliage. The small cream flowers give way to black fruits that ripen from late summer into autumn and persist into winter. Mature palms flower annually once trunk formation is well underway.
Detailed Descriptions
Foliage Description
gray-greenGrowing Conditions
Sun Requirements
Requires 8-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grow Washingtonia filifera in full sun in deep, well-drained soil, with room for a crown 10-15 feet (3-4.5 m) wide. It withstands desert heat, alkaline and saline soils, and drought once established, though regular water speeds growth. It is hardy to about 15-18F (-9 to -8C), tolerating more cold than other fan palms, while prolonged frost damages the foliage. Deep, infrequent irrigation during the first few years builds a strong root system. Yellowing older fronds can be removed, while green leaves are left in place because they continue to photosynthesize. In lawns and gardens the heavy frond skirt is often cleared for appearance and fire safety.Pruning
Dead and yellowing fronds can be cut close to the trunk at any time of year, while green fronds are generally left in place. Removing the persistent skirt of old leaves reduces fire risk and rodent cover. Cutting into green growth weakens the crown and slows recovery.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
early spring