Nursery find expose! Whats beneath the surface? Does it matter?

[River's Edge]

I thought I would share a fundamental bias I have for approaching bonsai development. Whenever I acquire a new tree from a nursery , from collection, or from another bonsai enthusiast the first priority is to determine the condition of the roots and the substrate. Of course, I time the repot in accordance with the species and condition of the tree, time of year and or aftercare available. Thought I would share an example for those that might be interested. This is a Scotch Pine, acquired by a friend from a local nursery and picked up by me for a fun project on development. When I purchased the tree it was evident that the health was reasonable and I thought it had some potential for Bonsai. Beyond that, it was in a five gallon nursery container with what appeared to be compacted dark potting soil. No nebari were visible at the surface or could be seen by scratching below the surface. Although the trunk base had some flare and promise of thicker roots below. The tree was heavy to lift for its size and I suspected very congested roots in the round pot. Current size is 4 inch base and 40 inches tall with healthy but not compact foliage. Not sure of the exact strain but not grafted.
Here is what I found and why it was important to look. 1. better roots than expected. 2. lots of larger rocks 3'-4" in the pot. Take up space? add weight? Save soil? 3. Lots of black soft roots that needed to be removed. ( rotted from excess moisture?)
4. compacted anaerobic conditions primarily in the bottom portion. ( space between rocks filled with muck) 5. fairly compact root ball core that enabled me to secure the tree with bamboo inserted and tied into the Anderson flat. 6. was able to safely reduce height of root ball to less than 5 inches from 12 inches for development. 7. exposed some flair and thicker roots to develop nebari, removed thinner roots higher up out of place for nebari. Plan forward is to use 1/2 HBR in successive repots to further change out the soil and develop a finer root ball that is approximately three inches deep for future bonsai pot placement in a few years. A complete repot for conifer accomplished in three steps over 1 1/2 years approximately. #1 now ( with greenhouse after care) , #2 in fall 2021 and #3 in the spring 2022. The pictures are in the order the work was done.
In this and most cases, the sooner one begins proper development of a Bonsai suitable root ball, the sooner it will be able to thrive in a bonsai pot!

 

[Eckhoffw]

I love the movement on this tree.
Looks great now-will be awesome in the near future!

 

[River's Edge]

I love the movement on this tree.
Looks great now-will be awesome in the near future!

Thanks, I wanted to experiment with a scotch pine and was attracted to the bark and foliage color of this one. needed another tree in the nursery like an extra hole in the head, but it called to me.

 

[Adair M]

Frank, I saw a drastic reduction to the root ball, but I didn’t see any “bare rooting” to start the replacement of the core soil. Maybe I missed it? And, no teasing out 1/2 to 3/4 inch of fine roots all around?

 

[River's Edge]

Frank, I saw a drastic reduction to the root ball, but I didn’t see any “bare rooting” to start the replacement of the core soil. Maybe I missed it? And, no teasing out 1/2 to 3/4 inch of fine roots all around?

LOL That's right young fellow, I did not take a picture of each step. However, I did mention that I was leaving the 1/2 bare rooting for the next two steps Reduction was approximately 55 %. The original root ball was 11inches high. 1 inch was over cover above roots, 5 inches off the bottom , mostly space taken up by the large stones and fine muck in the bottom. ( thus the perception of a much larger reduction than actual. The sides were teased out after securing with wire and bamboo sticks prior to placing my bonsai mix beside the remaining root ball. This did cause a mixing of the two soil types, not the perfect approach Sometimes when I do nursery work rather than show work I get sloppy and really careless!
The core soil remaining is still draining well with seived granite and pumice throughout sea soil. not the normal nursery mix. No clay or large bark pieces to worry about. And I did tease out large dead roots that I spotted. As I mentioned in the post, the condition of the roots was way better than I had expected. I will still want to switch out for my normal mix over the next two sessions as stated. I will adjust my watering routine initially to keep zones within the Anderson flat similar in moisture content.