There are around 30 to 40 tree species from the ulmus genus but the most common bonsai species used for bonsai is bonsai elm parvifolia or Chinese elm bonsai. They are favoured by beginners because they are the hardiest in comparison to other elm bonsai. Still, enthusiasts who love challenges have cultivated other elm bonsai species and succeeded in it. In this article, I will list those other species that can be cultivated as bonsai and will compare them with Chinese elm bonsai. I will focus on the Characteristics, care requirements, and suitability as a bonsai.
Let’s start with Chinese elm bonsai or;
1) Chinese elm bonsai or bonsai elm parvifolia :
Characteristics:
- Common name: Chinese elm or lacebark elm bonsai.
- Leaves: The leaves of Chinese elm are usually a deep green color, shiny in texture, and are arranged in the leaflet alternately.
- Twigs and bark: Greyish brown in color. Smooth at a young age and will develop roughness with age. The trunk has a lace-like texture and because of that, its other popular name is lacebark elm.
- Fruit and flower: They do produce white flowers and dry brown samara as fruits but it’s not common in bonsai.
- Growth habit: Vigorous, upright, and good crown density.
Care Requirements:
- Light: They are semi-indoor bonsai, meaning they can survive both indoors and outdoors. Filtered sunlight is best for this bonsai.
- Water: They love it when their soil is slightly moist. As a general rule of thumb water when the topsoil is dry to touch is ideal. But, they do endure draughts to some level.
- Lacebark elm Pruning: They are good with heavy pruning and will forgive your mistakes during pruning.
- Pest and disease: Compared to other elm bonsai they are resistant to pests and disease.
Suitability As A Bonsai:
Chinese elm is the perfect tree for bonsai. They have a compacted nature, they can endure different atmospheres, they are indoor-outdoor and resistant to pests and diseases.
2) Siberian Elm (Ulmus Pumila Bonsai):
Characteristics:
- Common name: Ulmus pumila bonsai.
- Leaves: Leaves of ulmus pumila bonsai are organised alternately along the branches. They are small, oblong, toothed, pointed at the tip, and slightly tilted at the base.
- Bark: The bark is a pale gray-brown with distinctive grooves and in the wild, it is often streaked with stains caused by bacterial wetwood.
- Flower: Produce reddish-green flowers between March and May. It’s not common in bonsai.
- Growth habit: Mature trees have grey trunks and weeping branches. Their trunks are brittle and in the wild, they easily break off by strong wind.
Care Instructions:
- Light: They need full sun to partial shade.
- Water: They need regular watering to thrive and love when the bonsai soil is slightly moist constantly.
- Pruning: They can handle heavy pruning to a moderate level. Try to prune in spring and summer when their growth is very much active.
- Pest and disease: They are resistant to such elm disease but can get attracted by elm beetles.
Suitability As A Bonsai:
Not as suitable as Chinese elm bonsai but they are arguably the second-best elm species used for bonsai cultivation.
3) American Elm (Ulmus Americana):
Characteristics:
- Leaves: Leaves are arranged in an alternative pattern, the arrangement is not complex, 3-6 inches long, around 3 inches wide, broadest at or base the middle with rough, sawtooth rims.
- Bark: Their bark is grey, in cross-section with lined brown and white layers, grooves deep, and ridges flattened with delicate closely clustered scales.
- Growth habit: A medium-sized tree that is in maturity with flaring branches creating a broad-spreading, fan-shaped canopy.
Care Requirements:
- Light: They do best in full sun.
- Water: They need constant watering and they are more vulnerable to droughts and over-watering in comparison to Chinese elm.
- Pruning: They grow rapidly like any other elm bonsai so you might need to prune them more than once a year to keep their shape.
- Pest and disease: They are suspectable to many pests and diseases, most particularly the Dutch elm disease.
Suitability As A Bonsai:
It’s only suitable if you are planning for a larger bonsai. Their leaves are large and they are susceptible to pests and diseases. These two drawbacks make them unsuitable for bonsai.
4) English Elm (Ulmus Procera):
Characteristics:
- Leaves: Deep green leaves that are rough to touch.
- Bark: Their bark is rugged, giving the appearance of years of struggle.
- Growth habit: Same as Chinese elm bonsai- upright, strong with a heavy crown.
Care Requirement:
- Light: They love the full morning sun to partial shade.
- Water: Less hardy in terms of watering in comparison to Chinese elm bonsai. They need regular watering without getting waterlogged.
- Pruning: Just like any other elm species they are okay with heavy pruning.
- Pest and disease: Like American elm, they are not prone to resist pests and disease, this is one of their major drawbacks.
Suitability As A Bonsai:
Their growth habit and structure make them fit for bonsai cultivation, but their sensitive nature towards pests and diseases makes them unfitting for bonsai.
Why Is Chinese Elm The Best Elm For Bonsai?
In comparison to the Chinese elm with these other elm bonsai varieties, the Chinese elm stands out for its stability, adaptability, and practicality for different bonsai styles. Its small compacted leaves and growth habit, pest and disease resistance, and sleek appearance make it a favourite among bonsai growers. While other elm varieties like the American, English, and Siberian elms each have their distinctive charm, they also come with challenges such as vulnerability to disease and unfitting characteristics such as larger leaf sizes. However, the choice of elm variety will rely on your preferences.