When one mentions the term palm trees, images of paradisiacal beaches or tropical settings come to mind, suggesting that it will never be possible to grow them in our latitudes...
General information
Many species of palm trees can withstand cold and even frost.
The longer the palms have been in the garden, the more resistant they are, sometimes happily beating the minimum temperatures given for each variety.
Similarly, a palm tree planted in the ground is much more resistant to the cold than the same tree in a pot, which should be wintered in a greenhouse or veranda. Finally, you should know that in case of a cold snap, you can protect the heart of the palm tree with a wintering veil or bubble wrap to preserve it. In the coolest regions, don't hesitate to keep the old palms which form a protective collar at the top of the stipe.
The most rustic palms
Here are some examples of palms that will find a place in your garden despite the cold:
Rhapidophyllum hystrix is one of the most cold-hardy palms with a temperature of -25°C! It owes its adjective to its stipe covered with fibers dotted with protruding spines. The said stipe does not exceed one meter in height which makes it an ideal subject in small gardens, its leaves are wide (1,20 m) in fan and brilliant green. This palm appreciates humid soils where it grows in its regions of origin (Mississippi, Florida, California).
Trachycarpus fortunei is much better known than the previous species and for good reason! The hemp palm, as it is commonly called, is the most cultivated palm in our gardens, where it can tolerate frost episodes down to -18°C. Native to the forests of Central China, this fast-growing palm can reach 15 meters in height! Its broad (1.20 m), palmate leaves are a beautiful dark green. The stipe is covered with interlaced brown fibers protecting it from the cold.
Nannorrhops ritchieana is able to survive at -20 °C. This beautiful and slow growing palm has beautiful bluish leaves, enhanced by a kind of orange 'fur' around the base of each petiole. This palm tree native to the semi-desert mountainous areas of Afghanistan, Iran and Pakistan can reach 10 meters in height.
Washingtonia filifera is also well known in our gardens, because it likes most of the soils and grows very fast, reaching 18 meters in height and 1.20 m in diameter. Its massive and vertical stipe is covered over time with dried out palms forming a petticoat that falls under the crown. The shiny green palmate leaves see the emergence each year of arched inflorescences of 4 meters in length bearing cream flowers. The petticoat palm is frost resistant up to -10 ° C when well established.
