Tree
Mexican Fan Palm
Washingtonia robusta · Arecaceae
Also called: Mexican Washingtonia, Skyduster, Mexican Sky-duster
Mexican Fan Palm (Washingtonia robusta) is a low-water tree well suited to Tucson and the low desert. It thrives in full sun.
Mexican Fan Palm at a glance
- Water use
- Low (established)
- Sun
- Full sun.
- Mature size
- 60-100 ft H x 10-15 ft W (very tall, slender trunk with a compact crown).
- Growth rate
- Fast.
- Bloom
- Creamy white flowers on long arching stalks., Late spring to summer; small black fruits follow.
- Cold hardiness
- USDA zones 9-11; hardy to about 20-25 F, slightly less cold hardy than the California fan palm.
- Soil
- Adaptable to most soils including sandy and alkaline desert soils; tolerates moderate salinity with adequate drainage.
- Native range
- Native to Baja California and Sonora, Mexico (not native to Arizona); naturalized and very widely planted across the Southwest.
- Best used as
- Tall vertical accent / skyline palm, Lining streets and drives, Resort and oasis landscapes, Quick screening height
- Wildlife
- Fruit eaten by birds; old fronds and crown provide nesting/roosting sites.
- Toxicity
- Non-toxic. Leaf-stalk teeth can scratch; falling fronds and dropping fruit are a litter concern.
How to grow Mexican Fan Palm in Tucson & the low desert
Watering
Drought tolerant once established but grows faster and looks best with deep periodic irrigation; water deeply every 2-4 weeks in summer, less in winter. In native habitat it grows near water, so supplemental water keeps fronds lush.
Fertilizer & nutrients
Apply a palm fertilizer with potassium and magnesium 1-2 times in the growing season to prevent frond chlorosis; supply manganese/iron in alkaline soils to avoid deficiencies.
Pruning & care
Remove only dead brown fronds and spent flower/fruit stalks (annually); leave the green skirt for trunk health. Wear gloves—petioles have curved teeth along the margins.
Notes
Taller and far more slender than W. filifera, with a thinner trunk and a smaller, brighter-green crown. Self-seeds prolifically and can become weedy along washes and in irrigated areas; its great height makes mature-tree pruning a hazard. Hybridizes with W. filifera ('Washingtonia filibusta').
Sources: University of Arizona Cooperative Extension; ASU Desert Plants database (C. Martin); AMWUA Landscape Plants for the Arizona Desert; Palmpedia