The Chinese Windmill Palm brings tropical flair to cold gardens

Trachycarpus fortunei Image by Peter H from PixabayTrachycarpus fortunei Image by Peter H from PixabayThe Chinese Windmill Palm is widely grown in warm-temperate and sub-tropical regions, but is also known as one of the most frost and cold tolerant palms. Find out how easy it is to grow below.

The windmill palm has been cultivated for so many centuries in China and Japan that it is not certain exactly where it originated. It grows wild at elevations up to 2,400 meters anywhere south of the Qin Mountains of Shanxii Province in north-central China, and westward through Sichuan and up to the edge of the Tibetan Plateau, with the very dense populations in the Yangtze River Valley. It is commonly called the “Chusan palm” after Chusan Island (now Zhousan Island) off the coast of China where it was first seen in cultivation by Robert Fortune, a famous Scottish botanist. Fortune smuggled plants from China and brought them to the Kew Horticultural Gardens and the Royal garden of Prince Albert in the United Kingdom. It was later named Trachycarpus fortunei, after him.

The species is also reported from Myanmar, Vietnam, India, Nepal, and Bhutan, where it is most likely naturally occurring. It is also found in Taiwan and southern Japan, but its occurrence here is most likely a result of cultivation. Nowadays this palm is commonly planted near human habitations as a shade trees, or close to cultivated fields, and in plantations. It also grows in natural forests, favouring warm temperate to subtropical mountains or hills throughout its range.

As this palm spread to the west it was found that it could even be cultivated in areas with distinctly cool temperate climates, including much of Europe, as least as far north as the UK and Ireland, and including: Belgium, Holland, France, Germany, Denmark, southern Scandinavia, and westward to Bulgaria and Crimea.

Today it is also widely cultivated in the northern parts of North America, and even further north to coastal British Columbia, Canada, and the coastal areas of Washington State. In the eastern USA it occurs from as far north as coastal Virginia, to the deep southern states. This palm is also found in Tasmania and New Zealand, where today it is considered an invasive species, and in Japan it has naturalised itself in low mountain forests.

The windmill palm is a beautifully compact evergreen, growing anything from 6.1 to 12.2m tall with a 2 to 2.4m crown, depending on climate and rainfall, and in its natural habitat it can reach 15m, tall, but takes around 20 years to reach full maturity. When young it has no stem but as it matures it develops a rather slender single stem about 30 to 35cm in diameter which is covered with a loose mat of coarse brown fibre. In mature specimens the fibre may slough away to reveal a smooth ringed surface. The large and handsome fan-shaped leaves spiral out in all directions from the top of the plant, resembling a windmill, hence the common name “Chinese Windmill Palm”. They are a mid-green in colour with almost silvery undersides, and are held on thin flattened stems which are sharply toothed along both edges. The dead leaves hang down from the top, forming a brown skirt.

The windmill palm's inflorescence erupts from a large packet-like bud in early spring or summer, forming large, branched and drooping spikes that are held within the crown. The plant is generally dieocious, meaning it bears male and female flowers on separate plants, and the male flowers are yellow and the female flowers are a greenish colour.  While normally dieocious, individual trees have been shown to sometimes grow both male and female flowers. The male flowers are followed by small kidney-shaped fruits which ripen from green to blue-black, and the female plants bear small round blue fruits.  The fruits are dispersed by birds, wind and gravity.

Uses:

Trachycarpus fortunei is cultivated for its many uses. The fibres cloaking the trunk are used to make ropes and cloth, and it's coarse but very strong leaf sheath fibre is used for making brushes, ropes, sacks and coarse cloth. Mats are made from the bark, mixed with stem fibres, and leaves are woven into hats and fans. The wax derived from the fruit exterior, can be used to make polishes, wax paper and carbon paper.

In the Garden:

This species was awarded the Royal Horticultural Society Award of Garden Merit, and is used ornamentally around the world to bring tropical flair to the landscape,  especially in cold areas where more tropical species won't survive. However it is also used in many different types of landscapes, and especially in modern designs.

Gardeners who know and appreciate palms utilize this species where they want a single trunk fan palm that doesn't get too large and is easy to grow. Because of their narrow trunks and small crown size, the fan palm is great to plant close to buildings or walkways, and looks majestic as an avenue or street tree.

In smaller areas this palm can be planted as a single specimen, and in larger spaces it looks most effective when planted in groups of three or more. 

If you are planting windmill palms amongst other palms or large shrubs, make sure that the tree does not get totally shaded out, because although windmill palms will tolerate some shade they essentially require lots of sunlight.

Windmill palms are lovely specimen plants for large pots and their attractive foliage is sure to attract attention if the pots are used to frame an entrance or doorway, or are placed around swimming pools, patios or water features.

Because fan palms are fairly low maintenance and aren't threatening to passer-by's they are an ideal choice for retail stores, commercial projects and shopping centres.  Interior malls can utilize Trachycarpus if there is adequate air movement and sun.   

Avenue of Windmill Palms. Picture courtesy Scott Zona see his flickr pageAvenue of Windmill Palms. Picture courtesy Scott Zona see his flickr pageCultivation/Propagation:

Trachycarpus fortunei is widely grown in warm-temperate and sub-tropical regions, but is also known as one of the most frost and cold tolerant palms. Young plants can be damaged by -8°C, but mature specimens have been known to withstand snow and temperatures as low as -15 to -20°C without a problem. In very cold regions it is best to site the plant where it is sheltered from freezing winds, which can shred the leaves, making the plants look a bit miserable.

It thrives in regions with good summer rainfall and in more arid regions, and winter rainfall regions, it will looks at its best in the garden if it is watered moderately during summer. It is remarkably salt tolerant and can be planted behind the first line of dunes, or against a structure that will shield it from direct exposure to sea breezes. On very windy sites the fans tend to become tattered and unattractive.

The windmill palm loves full sun but will take some shade.  It prefers moist, rich soils with good drainage, but will survive in almost any garden soils except continuously soggy conditions; adapting to light (sandy), medium (loamy) and heavy (clay) soils. The plant prefers acid, neutral and basic (alkaline) soils.

Although remarkably drought hardy once established, the windmill palm will grow quicker if watered and fed regularly during the growing season. As with most palms, growth is slow during the first three years and speeds up after that. Once established feeding is not necessary unless you are growing it in a pot.

The only maintenance it requires is perhaps an annual removal of dead leaves, which if left in place, will hang down to lie flat on the stem, slowly forming an attractive 'skirt' of dead leaves, all the way up the stem. Many gardeners prefer to remove the dead leaves regularly but many will prune them out until the stems become rather tall and more difficult to reach, then they leave them on the plant as nature intended, because this skirt of dead leaves provides wonderful shelter for garden birds to build their nests in.

Palm seeds remain viable for three months, and they can easily be propagated by seeds sown in spring when the temperature are around 25°C, without a lot of fuss. All that is required is patience, as even fresh seed can take two to three months to germinate. Remember, the plants are dioecious, so both male and female plants must be grown if seed is required. The plant is also not self-fertile and is pollinated by insects.

To speed up germination, scarify the seeds, or pre-soak them for 24 hours in warm water before sowing. Sow them in small containers or seedling trays and cover with a very thin layer of soil. Water and place it in a very warm and humid place with good light. Once the young plants have developed proper root systems and at least three to four sets of leaves, they can be transplanted into bags to grow on.

Problems, Pests & Diseases:

If grown correctly the windmill palm suffers from no serious insect or disease problems.

Root rot can become a problem, and can cause the tree to die suddenly and completely, but this condition is rare.

Inadequate light or the loss of light exposure from surrounding plants is a common cause of decline of this genus.

Warning:

Trachycarpus fortunei is not listed as toxic to humans cats or dogs.