Growing palm trees isn't just possible in the southern parts of the United States. There are certain species of palm trees that can take some fairly significant cold and still thrive. These palms, also known as cold hardy palms, are becoming more popular in central and northern parts of the United States. Even some locales in Canada have a climate favorable for cold hardy palms to thrive. With a little protection in the winter months, you can enjoy your palm trees all summer long.
Purchase a cold hardy palm tree that is well-suited for your climate. Needle palms and dwarf palmettos are very cold hardy, however require a hot summer to grow. The chinese windmill palm is not as cold hardy as the previous two but grows well in areas with cooler summers.
Plant your palm in a good microclimate for your location, like an area of your yard that stays warmer relative to the rest of the yard. Planting your palm along a south of southwest facing wall is usually a good bet.
Fertilize your palm tree with a high quality palm fertilizer that contains micronutrients. Fertilize heavily in the spring and lightly in the fall for best results.
Pound four stakes into the ground around the palm in the fall, so that the fronds are completely inside the stakes. The stakes should form a square around the palm tree.
Wrap metal mesh around the outside of the stakes. Secure it to the stakes with small pieces of wire. Overlap the seam a few inches and secure the metal mesh to itself with wire also. The mesh should be a few inches higher than the top of the palm tree.
Wrap a lining of 6 mil polyethylene plastic around the outside of the metal mesh. Overlap the seam on the plastic a few inches and secure to itself with packaging tape.
Stuff the inside of the cage with dried leaves. Fill until the leaves completely bury the palm tree.
Spread a few inches of mulch around the entire cage where it meets the ground. This will keep cold winds from blowing up and into the cage.
Lay a piece of plywood on top of the cage when it is either below freezing or raining. Remove the plywood on warm, dry days to allow air circulation into the cage.
Remove the enclosure once temperatures have stabilized and no freezing weather is forecast. Your palm tree should look as good as the day you covered it.