Washingtonia robusta

Geoff Stein - Author & Editor

Revision as of 09:09, 22 July 2014 by Geoff_blocked_old (Talk | contribs)

Pronunciation: wash-ing-TOE-nee-uh roe-BUST-uh


Common Name: Mexican Fan Palm, Feather Duster Palm

Washingtonia robusta is probably the most commonly grown palm in the US and one of the most recognizable palms in the world.

Appearance and Biology
  • Habit: solitary
  • Height: 100 feet
  • Trunk: partial or complete retained dead leaf petticoat, though in cultivation usually pruned clean or closely thatched; 16"-24" thick, grey (reddish when recently pruned); often leaning toward the west when very tall
  • Spread: 6'-8'
  • Leaf Shape: palmate
  • Petiole: long (about equal to rachis) and heavily armed with large, very sharp teeth
  • Foliage: deep, somewhat shiny green, stiff as young palm, but leaflets developing characteristic droopiness with age; some cottony fibers
  • Reproduction: monoecious and 'rampant'
  • Inflorescence: long, arching, dark brown
  • Fruit: spherical dark brown; 1cm
  • Seed: 4-5mm spherical black
Horticultural Characteristics
  • Minimum Temp: 20F, though moderate leaf burn at 25F
  • Drought Tolerance: very high
  • Dry Heat Tolerance: very high
  • Wind Tolerance: very high
  • Salt Tolerance: good
  • Growth Rate: very fast (fastest palm in California and one of the fastest in the world)
  • Soil Preference: extremely tolerant of a wide range of soil types
  • Light Requirement: full sun, though can grow well in deep shade for years
  • Human Hazards: falling leaves in winds dangerous to both pedestrians and cars; profuse seed production makes sidewalks slippery; petiolar teeth make pruning hazardous
  • Disease or Horticultural Problems: few
  • Indoor?: performs moderately well if bright light available, but a dangerous indoor palm