Ulmus pumila is a species of deciduous tree that is native to regions of Central Asia, India, Korea, and nearby regions. It belongs to the Ulmaceae family of trees and is often referred to as the ‘Siberian Elm’ and sometimes mistaken for its close relative, the ‘Chinese Elm’. It is one of the last trees still found in semi-desert regions around Asia.

The trees grow to 25 meters in height and have a bushy structure that spans out as they grow. The bark is a dark shade of gray and most branches have a yellowish tinge to them which is a common characteristic for this species. The leaves are mostly dark green but change colour to yellow during autumn and will bloom for a week during spring. Apart from this, the tree lives for anywhere between 60-150 years depending on the environment it is growing in.

As for rowing Ulmus pumila trees into bonsai, they are one of the most popular options thanks to the immense hardiness these species possess. They are very forgiving and perfect for beginners as mistakes will often not cause too much harm to the bonsai.

This guide will assist bonsai enthusiasts in learning more about the Ulmus pumila Bonsai Tree.

How long does it take to grow Ulmus pumila Bonsai?

Ulmus pumila bonsai are regarded to be slow growers, with a minimum estimated complete growth time of ten years. This is the projected time it will take for the seed to develop to the stage wherein you can cut it. However, the exact time required to grow it as a bonsai varies depending on factors such as temperature, water, etc.

To help you out, let’s go into some specifics about how to plant, care for, and grow your Ulmus pumila bonsai.

Position and lighting

Ulmus pumila bonsai thrive in full sun or semi-shade conditions as long as it is not too hot. They can withstand morning temperatures during the summer and spring but in direct daytime sunlight, can be brought into the shade. Apart from this, you can keep your bonsai outside during the winter months as these trees are quite hardy and will grow well. Although, if it is cold enough for the formation of frost, you should bring it in to an indoor heated area.

Temperature requirements

Ulmus pumila bonsai is quite tolerant which is one of the reasons they are so popular as bonsai. These trees can flourish in a wide temperature range and will do well as long as you avoid extremely hot or cold weather. That being said, the suggested range for optimal growth is between 60 and 70 degrees Fahrenheit. If temperatures fall too far below this, you might want to provide it with artificial heating.

Soil

The Ulmus pumila bonsai is not very problematic and as such, you can use most kinds of soil with this. Preferably, slightly acidic soil with a pH level of 6 is suggested for best growth. Also, make sure the soil allows water to pass through to avoid waterlogging and root rot.

Watering needs

Ulmus pumila bonsai require average amounts of water and too much or too little can be harmful to their growth. The best way to find out when to water you Ulmus pumila bonsai is by looking at the soil. If your soil is beginning to dry up, you should water it until moist. On the other hand, if the soil is wet, avoid watering until it dries up as it could lead to root rot.

The amount of water you should use also changed depending on the temperature and season. In the spring and summer months, you will need to water your bonsai once every 1-2 days to keep it healthy. In winter this changes and you can reduce the watering frequency to once every 3 days as your tree will be using up less water.

While keeping the right amounts of water is important, you won’t have to worry too much with the Ulmus pumila bonsai. This is because they are very hardy and some mistakes won’t lead to any immense problems in your tree’s growth.

Another thing you can keep in mind is misting. This means spraying your bonsai on the surface with light amounts of misted water. This will help in improving your tree’s foliage and also its overall health. That being said, it is not a substitute for watering and should only be considered an additional task.

Feeding

Feeding refers to fertilizing your bonsai and is an important factor that can promote growth immensely. This is because your bonsai grow in pots and may not naturally get all the nutrients it needs for growth. So, for the Ulmus pumila, you can use any common organic fertilizer and dilute it to half power for use. As for frequency, you can fertilize your bonsai monthly during spring and summer and can stop during winter.

Styles

Ulmus pumila bonsai is a slow-growing bonsai with a large trunk. As a result, most upright forms in medium to big proportions are suitable for these trees. It’s also possible to include relatively thin-branched trees into group plantings.

How to Plant and Grow Ulmus pumila Bonsai

You want to know how to grow and plant Ulmus pumila bonsai. Awesome! Let’s look at how to plant and grow your own Ulmus pumila bonsai in more depth.

Propagation

Cuttings are the most prominent form of propagation for Ulmus pumila bonsai. It is quite easy and can be done by most beginners as well. Apart from this, you can also use seeds but this is often more difficult.

Pruning and wiring

Pruning is an important part of growing a beautiful bonsai for any species. It involves trimming and cutting outgrowths to maintain the size and shape of your bonsai. As for the Ulmus pumila bonsai, as it grows throughout the year, pruning is one thing that is quite important for optimal growth. The tree is known to produce thick and complex networks of branches that need to be trimmed often.

The best way to do this is to allow your bonsai shoots to extend up to 5 nodes before you trim it back by 1-2 leaves. This will help maintain the more strong branches and buds and improve the look of your bonsai as well.

As for wiring, the Ulmus pumila bonsai should not be wired for too long. This is because it can often reduce the overall growth and strength of the bonsai. So, if you do plan on wiring your bonsai, make sure you remove it within 2-3 months.

Repotting

Repotting is another important process when it comes to growing a bonsai tree. As for the Ulmus pumila species, you should repot the trees once every two years when they are young. As they grow older, you can gradually reduce the repotting frequency. Repotting for these trees is imperative as they grow large roots that get intertwined and start to grow out of the closed root structure.

The process itself is quite simple and can be done even if you are a beginner. Start by taking out your bonsai from its pot along with all the surrounding roots and soil. After this, use trimmers to cut off the excess roots while making sure not to cut out too much. Once this is done, you can re-plant your bonsai and fill in the space with fresh soil. This helps in acclimating your bonsai to the smaller size and promoting its look.

Some things you should keep in mind regarding this is that repotting should be done in spring and you need to take extra care of your bonsai afterwards. This means using well-draining soil and providing ample amounts of water to ensure your bonsai has the nutrients needed to grow.

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How to Care for Your Ulmus pumila Bonsai

It is recommended to prevent Ulmus pumila bonsai from extreme hot or cold conditions during their early years. That said, they flourish in temperatures between 60 and 70 degrees Fahrenheit and can be kept outside. In terms of soil, any regular mix with a PH of around 6 would suffice.

For optimum growth, Ulmus pumila bonsai should be kept in semi-shade or full sun. However, keep them away from direct sunlight and strong winds during the day as it can lead to damage and burning.

You should irrigate and mist it on a regular basis to keep the soil moist. When it comes to repotting, these bonsai can be repotted every 2-3 years when they are young, and then at longer periods as they mature.

Pests & Diseases

The Ulmus pumila bonsai is quite hardy and can resist most pests and diseases well. As long as you keep your bonsai in good condition and well-watered, it should be able to grow fine. However, there is always a risk of infestations and for this species, Spider Mites and Scale are the most common. While these pests can be quite problematic, they are also easy to stop. Just use an alcohol swab or spray to get them out and keep your bonsai healthy.