Washingtonia Robusta is a very fast growing, architectural fan palm tree with a trunk that is swollen at the base, tapering to the top. It is the tree often seen in Hollywood movies and goes under the common names of Petticoat Palm, Mexican Fan Palm or Skyduster. They have large, green, fan-shaped leaves, which thrive in full sun and can grow as large as six feet long.

The Washington Palm can be planted close to the sea, because of its salt-tolerance, but it is only hardy down to about -5°C with some protection. They will not tolerate being planted in very cold or exposed sites.

The small fleshy flowers are produced in the late spring, followed by black-brown, small fruits. Each fruit contains a single seed with a thin, sweet pulp that tastes like butterscotch or dates. The lower leaves remain on the tree after they die, and create a brown, straggly covering beneath the living green leaves.

There is a hybrid called Washingtonia Fillibusta [Fillifera x Robusta] which has the best qualities of both parents. It has the cold tolerance of Filifera and the wet tolerance of Robusta.

Growing Requirements

Soil
Washingtonia Robusta will grow in most soil types, even in quite poor soils. Grow in full sun, though young plants will tolerate partial shade.

Size
It will ultimately reach 80 to 100ft (24 to 30m) in height and 10 to 15ft (3 to 4.5m) depending on the climate.

Propagation
The Mexican Fan Palm is one of the easiest palms to grow from seed and the seeds can germinate in as little as two weeks, but this would be reliant on a high germination temperature, maybe as high as 40°C. Decent germination is achievable at 25°C to 35°C. Soak the dry seeds for 2 to 3 days in warm water before sowing.

Family: Arecaceae
Subfamily: Coryphoideae
Genus: Washingtonia