How do you make a root-over-rock bonsai? Practical experience shared with you

  A root-over-rock bonsai is made by exposing thick roots and letting them cling to and grow over rocks, with some bonsai accessories appropriately chosen to embellish it. It has the imposing air of standing atop a peak, giving people a feeling of indomitability, ceaseless upward striving, and unending life. Now I offer a bit of practical experience from my own process of making root-over-rock bonsai to the many bonsai enthusiasts for reference only.

  First, pay attention to choosing materials and selecting the tree roots: choose a stump with good growth vigor, sturdiness, tall fibrous roots, and ideally 5-6 relatively thick long lateral roots. For choosing the rock: choose one with hard texture and good grain, with many wrinkles on the surface, and it is even better if the roots can fit into the natural grooves of the rock, such as Hua'an stone (also known as Jiulongbi stone). For choosing the pot: choose a shallow bonsai pot.

  Next is the planting process. Before planting, trim and smooth all the root surfaces that will be covered by the pot surface, so as to help the wounds heal later. Clip the roots of the chosen stump onto the rock, comb the tree roots downward one by one along the grain of the rock, allowing appropriate natural crossing, and use thin iron wire or string to bind the roots and the rock tightly together. Choose a shallow bonsai pot, and when filling soil, follow the usual practice of ensuring good drainage; place the bound root-over-rock stump in an appropriate position in the pot. If the rock is relatively tall, fix the bottom of the rock firmly to the bottom of the pot with cement glue to prevent the rock from tipping over. Then fill with somewhat fine sandy soil until no more can be added to the pot surface, then use relatively thick plastic sheeting to raise the level from the pot surface up to the stump head, and fill soil up to the stump head as well. The soil is best made of pond mud and sand at 3:2. Press the soil as firm as possible so that the soil and the tree stump's roots are tightly combined, which is good for root growth.

  After potting, water thoroughly once, observe the pot soil, and wait until the soil is slightly dry before watering again. A newly planted stump itself does not have a large transpiration rate or water requirement. Prop the pot up with bricks to help drain excess water and also to help aeration. The pot should be placed in a wind-sheltered, shady spot without direct sunlight. Water the trunk once each in the morning and evening to ensure the trunk's water supply, create a good growing environment for budding, and let it slowly receive sunlight to adapt for a period of time. After that, it can be placed in a spot with ample sunlight for normal care. Watering must follow the principle of “water when dry, stop when wet.” For a newly potted root-over-rock bonsai, it is best not to fertilize, because the root wounds of the bonsai have not yet healed, and the fertilizer concentration is hard to control; if done poorly, it can burn the stump to death or rot the roots, making all the previous effort wasted. With such careful care, after the stump survives, you can carry out detailed pruning, shaping, and wiring according to the tree form into various styles of root-over-rock bonsai.

  Finally, you can remove the raised plastic sheeting from the pot surface and use tap water to wash away the soil on the rock. In this way the thick roots are exposed, and a beautiful root-over-rock bonsai is initially completed; at that time you will experience the joy of success.