These members of the birch family are well suited for bonsai. Hornbeam bonsai trees (Carpinus) are popular in Japan and throughout the West. These trees have bright green leaves, beautiful trunks with grey smooth bark, and leaves that turn pretty colours in the autumn. The bark and buds are attractive over the winter.
Hornbeams are found in temperate areas throughout the world, particularly in East Asia. China has the most species of hornbeams.
In case you are wondering how they got such an odd name, these trees are renowned for their extremely hard wood, which has been compared to horns. “beam” derives from the German word for tree, which is “baum”. The trees are also commonly known as ironwood.
These pretty trees are frequently grown for shade in landscapes. They attract wildlife, including deer, rabbits, swallowtail butterflies, and songbirds, and children like to climb on their low-growing branches.
Care Guidelines For Hornbeam Bonsai
Keep your hornbeam bonsai outside in the sun or part shade until the temperatures start to drop. A combination of morning sun with afternoon shade is ideal. While large hornbeam trees with deep roots are very tolerant of frost, the roots of plants in containers are susceptible to chilling and need to be protected from frost. Harsh freezes can kill them. If possible, the plants should be kept outside over the winter. If the weather will be particularly cold, you can put your bonsai trees in an unheated garage or shed. If you do move them inside – even to a garage – use a humidity tray to keep the air around these trees moist..
You must water hornbeam bonsai as soon as the soil gets dry. Water thoroughly until it runs out of the bottom of the pot. You may need to water them daily during the growing season. However, do not overwater your hornbeam bonsai, or it may rot. Keep the plant slightly moist during the winter. Avoid using water that contains a lot of calcium.
Soil And Fertilizing
During the growing season, apply a liquid fertilizer weekly, or add solid organic fertilizer once a month. Be sure that the fertilizer contains the appropriate micronutrients that plants need.
Regularly trimming your bonsai tree will keep it short and help the trunk to grow thicker. Prune the larger branches in the spring before the new buds open. You can remove large terminal buds. Once the new shoots have matured, shorten them to two leaves. This will encourage a second round of leaves to grow. They will be shorter and more compact and will ensure that the tree remains vigorous. If you prune in the autumn or winter, keep the buds on the twigs. Be careful not to remove all the new growth. Remove large leaves as they appear.
You have a choice of growing new plants from seeds or cuttings. Seeds can be planted outside in the autumn. If you choose to grow new plants from cuttings, take them from the softwood during the middle of the summer.
Potential Pests And Diseases
Keep an eye out for mealybugs, little fuzzy white blobs, because they hide in the crevices where the leaves grow from the shoot. If you catch them early, use a Q-tip with isopropyl alcohol to kill them. Powdery mildew is a fungal disease that turns the leaves white. A dilution of half milk and half water can be sprayed on plants to cure this disease. Scale can also be a problem and can be treated with neem oil.
If your plant is attacked by any of these pests or diseases, provide it with more light and air. Overwatering can cause root rot, which is typically fatal. If the leaves look scorched, your tree is getting too much sunlight.
Repot your hornbeam bonsai every two years in mid-summer. Older trees do not need to be repotted this frequently. Your plant will also let you know when it needs repotting by growing roots through the bottom of the pot. Remove the bonsai tree from its pot along with all the soil. Trim away one fourth of the root mass. Focus on pruning the straight, vigorous roots that grow at angles from the base. Pruning them encourages more branching roots to grow. Then you can either repot the tree in its original pot or plant it in a slightly larger one. Thoroughly water the plant once you have repotted it.
Wiring Your Bonsai
You need to be careful if you want to wire your tree. If you don’t remove the wire, it will bite into the smooth bark, leaving scars that you will see for decades. Consider using guy wires or strings instead.