If you live in an area that freezes over in the winter, you may think that having tropical plants in your garden is out of reach.
The truth is that there are several species of cold-hardy palms that can actually survive in below-zero temperatures.
Some are native to other countries, like the windmill palm (or trachycarpus fortune) from China; others, like the needle palm (rhapidophyllum hystrix), cabbage palm (sabal palmetto), and dwarf palmetto (sabal minor), are native to the Southeastern US, but can grow in other areas.
This means that even if you live in Minnesota, you can still turn your garden into a green and inviting tropical paradise.
The first step is to determine your plant hardiness zone. Another option is to create a protected microclimate, like a greenhouse, where you can create an artificial hardiness zone.
Once you have determined, or created, your hardiness zone, you can then find a list of the temperature minimums for the different species of hardy palms.
You might be able to find hardy palms at a specialty greenhouse however, you will have more luck purchasing them from an area where they grow and plant palm trees regularly.
Growing and Maintaining Hardy Palm Trees
Hardy palms should be planted in an area with southern exposure and good drainage.
Like most other trees, palms are the most vulnerable in the first three years. Even though hardy palms can survive in extreme cold, you should still take care to protect them as much as possible in the first few years – until the trunk has doubled or tripled in size, and the roots have taken hold.
One method is to cover the young palm with an old sheet, or blanket, during the winter months. However, you may not need to cover the plants for the entire winter, depending on the following factors:
Daytime temperatures – if the temperatures are regularly above freezing, you may be able to keep the palm uncovered during the warmer days;
How long the temperatures are at or below freezing – if it’s only a matter of a day or two, you may be able to leave them uncovered; and,
The amount of sun exposure – if the temperatures are above freezing, and the plant gets several hours of direct sunlight, it could actually be more beneficial to keep it uncovered.
Here are a few other things you should consider, when planting your palm:
Palms should be planted in neutral soils. If your soil is too acidic, or too basic, you will need to treat it prior to planting;
Palms should be planted in an area where the roots will have room to spread, undisturbed;
During the summer, you should water and fertilize the palms regularly, which can help them thrive in the warm months, and survive the cold months;
When pruning, only cut of the dead fronds that are hanging straight down. Do not cut all the way down to the trunk, instead leave a short portion of the frond attached, to reduce damage to the trunk;
You should also remove the flower and fruit stalks, when the plant is young, which will stimulate vigorous growth, however,
If vigorous growth is not an issue, you can leave the flower and fruit stalks intact. In fact, in some cases, you can even use them for food.
As you can see, with a little work and care, you can grow palm trees in almost any area. You can find more information on edible palm s from the California Rare Fruit Growers or from resources like Eat the Weeds.