The Chinese elm bonsai is a versatile and adaptable tree that makes a classic selection for bonsai. Reaching up to 60 feet in its natural elements, the Chinese elm produces mottled, reddish grey bark with shiny, dark green foliage. Its moderate growth rate allows the Chinese elm to respond well to timely pruning when accompanied with generous care.
Sterilise your pruning shears before beginning pruning. Wipe and thoroughly clean your shears with alcohol or hydrogen peroxide. Keep your sterilizer handy during pruning as you may need to sterilise between cuts.
Remove unhealthy branches from your Chinese elm bonsai to redirect your bonsai's energy to more viable areas. Complete this process in the early spring before the onset of the growing season. Remove all dead, diseased and damaged branches. Sterilise your shears between each cut to prevent spreading disease throughout the tree.
Study the shape of your bonsai after you have removed the deadened branches. Identify the desired shape that you want to create for your Chinese elm bonsai. Choose a shape that complements and enhances the bonsai's natural shape for best results. Train your elm bonsai over the course of several growing seasons to allow the bonsai time to grow into its shape. Avoid pruning more than one-third of your elm's healthy branches to prevent growth stunt.
Trim your Chinese elm bonsai periodically throughout the growing season. Maintain its shape by cutting back vigorously growing sprouts around the trunk and branch elbows. Trim back one or two sets of foliage on each branch after allowing the branch to develop two or three new sets.
Repot your Chinese elm bonsai about every two years during the early spring, just before bud swell. Repot sooner if needed to avoid a root-bound system. Prune the roots of your Chinese elm during the repotting process.
Inspect the root system closely after removing the excess soil from the root mass. Use a sterile root hook to comb away about one-third of the root mass. Cut away damaged and deadened roots with sharp, sterile shears. Trim back no more than one-third of the root system so that the system is balanced with the bonsai's trunk, branches and foliage.
Root prune and repot your Chinese elm bonsai quickly to prevent the roots from drying. Clean your bonsai's container with warm water and soap, and allow it to dry. Create a loamy soil environment by incorporating equal parts of nutrient rich soil, organic matter, such as pine bark and peat moss, to improve water retention.
Line the bottom third of your elm bonsai's container with a layer of soil mixture. Position your elm in the centre of its container and fill the remaining two-thirds of the container with soil. Press the soil firmly around the base to secure its position.
Soak your Chinese elm bonsai immediately after repotting to promote a good establishment. Place your potted bonsai in a sink and fill it with tepid water. Allow the water to reach slightly beyond the top surface of the container. Let the bonsai sit in the water until bubbles stop rising to the surface. Remove the bonsai from the sink and allow it rest until the water no longer flows from the drainage holes.
Keep your Chinese elm in a warm, sunny location. Make sure that the location is well-ventilated and provides plenty of full sunlight.