I have been using this technique now for over ten years and I have finally decided to share what I have learned in these videos. The technique is known as ‘sweating’ and is used extensively in arboretorial circles. I use for the following species: Cratageus, Prunus, and most of the Rosaceae family, do not use on evergreen species.
I collect trees with as much root as possible, but I have put roots on trees that have not had any.
Follow this procedure and your success rate in establishing your freshly collected yamadori will improve immeasurably.
Collect as much root as possible
Clear as much mountain soil but do not wash the roots
Use the soil mix as shown below
Clean cut the major roots as close to the trunk without spoiling the nebari
Place the tree in the smallest container possible
Ensure that the tree is well packed in the container
Wire the tree securely in the pot
Make sure that the cut branches are clean and NOT SEALED
Saturate the soil
Pile fresh sphagnum moss on the surface of the container
Wrap the whole tree in a VERY large black plastic bag
Place in a sunny position as the tree MUST GET HOT
Humidity in the bag must be high at all times, mist spray daily
After two or three weeks new buds will appear particularly around the cuts
Ensure that they do not touch the sides of the bag.
When the new shoots reach 5cm or 2” remove from the bag and protect from cold and wind, mist spray daily and keep out of direct sunlight.
Keep watch for the new shoots hardening off, then you can feed with a very diluted solution; do not work the tree for the first 12 months.
Good luck, please do not copy these photos or the text, and share the link freely.