How to Rock-Plant a Bonsai
- 1). Choose or prepare a bonsai tree that's well-suited for rock planting. It is important that the tree have long and tough roots. To prepare a plant so that its root system will be adequate, grow the tree in a thin, tall pot for a while. If the root system is not already adequate, it will probably take a year or more of growing before it will be ready. Some of the best bonsai trees for rock planting include Chinese elms and strangler figs.
- 2). Choose a good rock. It is important to make sure that the rock conveys the look you are trying to achieve and that it fits the type of tree you have chosen. A round river rock, for example, would not suit a coniferous tree; that type of rock would suit a willow much better. Scoria is a good all-around rock, as is the Japanese Ibigawa rock. You will have to judge which will fit your tree the best.
- 3). Remove the soil from the tree's roots as gently as possible. It is best to remove as much soil as you can with your hands, then wash the rest away. Do not cut more roots than is necessary.
- 4). Attach the tree to the rock with grafting tape. Put the tree in a natural place. Try to place the roots in the path of least resistance down the rock's face.
- 5). Place the tree in a bag or pot and fill it with soil, covering the roots completely. A thick plastic bag will allow you to roll the edges down as you remove the soil later. Water the tree. Prune the top branches in a manner that fits with any pruning you may have done on the roots so that the top of the tree will not overwhelm the roots' capacity.
- 6). Gradually remove the soil from the rock face. This is a process that can take a couple of years, so do not rush it. The roots need soil in order to grow thick and tough, so remove the soil carefully and patiently.
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