Washingtonia filifera

An amazing and easy-to-grow tree that should be in every landscape! The Hardy Fan Palm is native to Southern California and is tied with several other species as being the most cold hardy Palm. They are listed for growing in zones as low as 7b or 8a which would mean they are hardy to around 10 degrees, however they can survive much colder temperatures as long as it is not every year. A few winters ago we had -5 degrees and although the palm leaves had some frost damage the trees quickly produced fresh new leaves in the spring. But if cold temperatures like that occur every winter the trees often end up being dwarfed and may only reach five or six feet tall.

Of the hardiest of the two Washingtonia available species, this species, with its stout trunk and large leaves adorned with white threads, is the most northern -- this seed collected from stately specimens near city hall in the town of the same name where temperatures of 0 F can defoliate but not kill these lovely plants. Keeping in mind those dips were brief and their winter climate is dry, these are quite possibly the most worthy of trying in the marginal zones where they have not yet been successful. Full sun…a little extra water in summer to boost growth. To 30-40 ft so give it some room.

Among the palms planted at the Ruth Bancroft Garden is a trio of Washingtonia filifera, the California Fan Palm. This is the only palm native to California, and it occurs in Arizona, southern Nevada and northern Baja California as well. Although it grows in desert areas, it is invariably found near springs or water courses, where the roots have access to water. The California Fan Palm is closely related to the Mexican Fan Palm, Washingtonia robusta, which is the species commonly planted along streets in Los Angeles and other warmer parts of California. However, Washingtonia filifera differs in being a stouter-trunked tree with somewhat larger leaves and longer drooping threads at the tips of the leaves. It is also more cold-tolerant than its slimmer cousin. As with many kinds of palms, the leaf-stalk of Washingtonia filifera is very tough and edged with sharp teeth. As the leaves wither and die they do not drop off. Instead, they droop down and form a brownish-gray ”skirt” below the crown of the tree. These old leaves are sometimes removed, but at the Ruth Bancroft Garden we prefer to leave them in order to keep the natural look of the trees. In habitat, Washingtonia filifera normally flowers in spring, but in cultivation it may do so later, as is the case with our palm coming into bloom in September-October. The inflorescence is nearly the length of the leaves, with numerous slender pendulous branches bearing small white flowers. The fruit is a small purplish-black drupe, which was important as a food source for Native Americans in the region where it occurs.

A cold hardy palm good to Zone 7-10. These are wild collected seed grown plants. They are heavy trunked to 60 ft. The fan leaves are 6 to 8 ft. wide with white threading between the segments. To see a photo of a mature Washingtonia filifera go to http://www.pacsoa.org.au/palms/Washingtonia/filiferaH.html

California fan palm is the only palm native to the US Southwest, and is a popular, outstanding ornamental; growing quickly and easily from seed. Truth or Consequences (along with Alamogordo) is probably the coldest place in the world where W. filifera has been known to flower and set seed, enduring temperatures below 5°F many winters. Plants grown from seed of these trees have shown superior performance in Albuquerque. These palms survive there because summers are hot, winters are dry, and plants are acclimated gradually to the cold weather. If you ever wanted a shot at growing W. filifera in a cold climate, get some seed while it's fresh!