Koyo Bonsai Concave Cutters

Unlike standard bypass pruners that leave a flat cut, concave cutters have a curved blade that removes a small, circular section of wood. This creates a depression in the branch collar, which encourages the tree's bark to grow over the wound and heal flush with the trunk, preventing unsightly bumps or scars.

While these are professional-grade tools, they are essential for any bonsai enthusiast regardless of skill level. If you are serious about the long-term health and aesthetic of your trees, investing in a proper concave cutter early on will save you from having to correct poorly healed pruning wounds later.

With an overall length of 10.75 inches, these cutters are designed for medium-sized branches. While they are robust, you should avoid forcing them through branches that are too thick for the jaw opening, as this can damage the precision alignment of the blades.

To keep them in top condition, wipe the blades clean of sap and debris after every use using a soft cloth and a light oil. Store them in a dry place, and avoid cutting wire or hard, dead wood, which can chip the precision-ground edges.

Yes, these Koyo cutters are manufactured in Japan. They are crafted with the high-quality steel and precision engineering typical of traditional Japanese bonsai tools.