Vol#17 Leaf Pruning, Leaf Cutting, and Leaf Thinning: Perfecting Your Bonsai Care Routine

As the temperatures rise, the mountains' trees welcome the arrival of fresh greenery, and the bonsai trees begin to flourish with fresh foliage. During this season, there are various care tasks related to leaves. Yet, you may be wondering what kind of work is best suited for your bonsai trees.

Understanding these tasks unique characteristics will help you determine the most suitable ones for your bonsai trees. Let me introduce some of them:

First, let's talk about "Leaf pruning". This is a common practice for cultivating Maple and Zelkova bonsai trees during the cultivation stage. When it comes to leaf pruning, there are two main approaches. The first is "Total pruning," which involves cutting off all the leaves once the new buds solidify. The second method is "Partial pruning". You trim the stronger outer leaves while leaving the rest intact.

By pruning the bonsai tree’s first leaves (primary buds) that appear in the year, you encourage secondary buds to sprout from the nodes. It will lead to increased twig development and faster branch growth. Additionally, the secondary buds produce smaller leaves.  If you repeat this process over several years, it can help reduce leaf size.

The main purpose of leaf pruning is to reduce leaf size and promote twig development. As the bonsai tree reaches a mature stage, this type of maintenance becomes unnecessary.

Furthermore, it is important to enhance the tree's vigor. Thus, make sure to apply fertilizer effectively before the budding stage. It will boost the tree's energy before proceeding with the pruning.

Next, let's discuss "Leaf cutting" and "Leaf thinning". Both tasks aim to prevent leaf scorching, ensure proper sunlight exposure, and airflow. They are essential practices for maintaining a healthy and mature bonsai tree.

Leaf cutting should happen from when the leaves solidify until the end of the rainy season. During this period, you trim the existing leaves one-third to half of their original size. By reducing the leaf surface area, you can control transpiration, thus preventing water stress.

Similarly, leaf thinning happens during the same period. In this practice, one leaf is removed from each pair, reducing them to a single leaf. It is advisable to leave the leaves positioned towards the outer side to maintain a balanced appearance after leaf thinning. This will also help with, transpiration control and prevent water stress.

In recent years, the intensity of summer sunlight has increased. Let's make good use of leaf pruning and leaf thinning techniques to ensure a successful transition through summer.

Until next time

ReBonsai　Yusuke Ogawa

Unlock the Art of Pruning with Yasugi Steel Bonsai Scissor Series