The Chinese Windmill Palm, also known as Trachycarpus fortunei, is a cold-hardy palm tree than can be cultivated as far north as Southern Virginia and Tennessee. This palm is known to withstand temperatures as cold as 0 degrees Fahrenheit for a brief period of time. For the best cold hardiness, you will want your palm to be healthy and a fast grower.
Things You'll Need
- Organic compost
- Organic nitrogen fertilizer
- Wood mulch
- Bungee cords
- C9 Christmas lights
- Thermostatically controlled outlet
Boosting Windmill Palm Growth
Remove all grass from around your windmill palm in a circle that is as wide as its canopy. Generally, this is how far the root system spreads out. It is important to do this because grass robs nutrients and moisture from your tree.
Amend the soil around the palm. Windmill palms prefer soil that is well draining and fertile. To achieve this, mix a few shovelfuls of organic compost and organic nitrogen fertilizer into the top two inches of the grass-cleared soil. This amendment is all natural and will not burn your plant.
Spread wood mulch around the windmill palm where you removed the grass and added the soil amendments. Mulch improves soil's water retention and works to keep weeds at bay, so your tree's roots won't have competition for water and nutrients.
Clear excess vegetation near your windmill palm. It will grow to between 10 and 20 feet tall and have a spread of 6 to 10 feet wide. Windmill palms grow best in areas that are part shade/part sun, however, they are tolerant of full sun when given plenty of moisture.
Water the palm frequently to keep the soil evenly moist. In periods of hot, dry weather, you will have to water the palm almost daily. Give it a good soaking each time you water it. This will help promote a deep, penetrating root system.
Pull the mulch back every month or so during the growing season and mix in more organic nitrogen fertilizer. You almost can't give plants enough of this in warm summer months.
Protect your windmill palm when the temperature falls below freezing. A simple, yet effective, protection method is to tie your palm's fronds up with bungee cords, wrap the trunk and fronds with C9 Christmas lights (larger bulbs) and then wrap it in burlap. Turn the lights on for heat when the temperature falls below 15 degrees F or when it will not top 32 degrees F for more than a day. Remove all protection when warm weather returns.
Put down 8 to 12 inches of mulch in autumn to insulate the ground if it regularly freezes. Remove in spring.
Tips & Warnings
- Windmill palms in fast-draining soil need more frequent watering than those planted in dense, clay soil.
- During colder temperatures, do not water frequently. This can induce root rot.
- For temperature automation, a thermostatically controlled outlet can be used to automatically turn the C9 Christmas lights on and off. Place the TCO under the burlap wrap next to the C9 lights and plug the lights into it. It will turn the lights on at 35 degrees F and off at 45 degrees F.
- Pests are not a huge problem for windmill palm trees. One threat is the palm aphid, which sucks juices out of the leaves, causing a yellowing of the fronds. Sooty mold grows on the honeydew they produce, which can reduce the palm's photosynthesis ability. These pests are easily managed by spraying horticultural oil on the palm.
- Winter protection is especially important if you have a few days that don't get above 32 degrees F during daylight hours. Consecutive hours below freezing can be more damaging than a rare night that gets as cold as 10 degrees F. The above scenarios will severely damage your palm if not protected.
How to Protect Windmill Palms in Freezing Weather
The windmill palm (Trachycarpus fortunei) is hardy in cold weather as low as 5 degrees Fahrenheit, so if you are growing one...