Root growth hormones after re-potting

Hello fellow Mirai-ers, I just re-potted a nursery stock Carmine Jewel Cherry. The roots were insane and strangling each other. The root mass was so dense, and jetting straight down. reducing was a big challenge. It was pruned back heavily and there was not a lot of roots left after I was finished. This was a real “kill it or make it a bonsai” moment. I re-potted it in a colander like hydroponic pot with akadama and pumice to encourage root recovery. My question is: Should I dilute root growth hormone to facilitate quicker recover in the roots? I don’t see Ryan talking much about this. Thanks for any help.

Harry Harrington in the UK has some article on this on his site. He uses it for Yamadori though. The product he uses is called Rhizotonic (which per the claim of the manufacturer is more than a simple root hormone).
Would be interested in the opinions/experiences of others here.

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I am experimenting with a product called Regal Crown. I use it at work when we transplant large trees and also when we lay sod in the heat of the summer. I have seen the results on both turf and our specimen trees. The product is not cheap at a little over $200 a gallon. I have started to use it on a satsuki that dropped in health over the winter. I’m seeing a turn around on it in less than a month.

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@antelion I dont know if you listen to the asymmetry podcasts, but recently Ryan had a soil scientist as a guest. He spoke of humic acids. They apparently that stimulate metabolic process of the trees and improve their relationship with the microbes in the soil. The humic acids essentially ramp up beneficial microbial activity, acidify the soil, improve the uptake of nutrients by the microbes as well as the plants, stimulate root growth and regeneration, speed up growth and development. And it goes on and on.
You tube link humic/fulvic acids

Im going to try using humic acids in conjunction with zeolite and my current organic fertilizers later this year or next repotting season. Amazon sells both for reasonable prices with free shipping.
[KMI Zeolite](KMI Zeolite Powder, 100% Natural Soil Amendment for Farming, Gardening, Golf Courses, Turfgrass, and Medical Cannabis
[Humic acid granules](Granular Humic Acid Powder - Organic - 25lb Bag


Those poor dinosaurs…

I need to listen to that podcast. Ryan is referencing it more and more and I’ll need to keep up.

How much of this do we mix into our bonsai soil? How much should we apply to the surface of our pots?


With a pH what?


@BillsBayou Great question! So the humic acids to my understanding are a form of sulfur and calcium. They are highly available to plant as they are chelated. So essentially, do not fertilize with products that contain high levels of sulfur or calcium due to risk of toxicity or shock. The humic acids are meant for soils with low levels of organic matter along with other soil types. I’m not sure how much to use, as I’ve not purchased this product yet but plan to start later this year. I would suspect the quantities would be small sprinkled on top at regular intervals i.e. weekly or monthly. I would also advise you test your soil/substrate of your plants prior to using humics. I’ve tested and had tested my soils/substrates and was very surprised. The soil is slightly alkaline and lacking in almost every nutrient. I suppose this is also thw point of bonsai soil… pumice and lava have almost no nutrient binding capacity and akadama is pretty low as well. In addition, the water I use is “hard” and full of lime… Binds everything up and the remainder washes out.
I’ve noticed in past 2 years that some of my bonsai have not been thriving as they had when I used more pine bark and DE. The few that are in pine and/or DE mixes are the most vigorous. Those substrates when tested and sent off for testing had a better “soil quality.” They were more acidic…pH was approximately 6.8ish and they had low but acceptable levels of nutrients and micro nutrients.
So what I started to acidify the water I use with vinegar to a ph of 6.0 and really upping the amount of fertilizers I’m using. The plants are responding well.
When next repotting I will likely move back to using pine bark, adding zeolite and substitute it for pumice which is far superior to pumice because of its CEC of around 200 and porosity. I sill maintain my lava, haydite, left over turface and DE. For select trees I will still use Akadama and akadama mixes.
Hopefully this will keep the pH more in the desireable range and prevent leeching of the fertilizwrs and nutrients while increasing their availability to the soil microbes and plants.

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Humates are made up of three molecular sizes, humins, humid acid and fulvic acid. Humins is not dissolvable in water and there usually not found in products we would use. But both humic and fulvic acids are, they are primarily made up of carbon. They each have different effects on the soil and effectiveness of assisting in making different nutrients more available. Over time repeated applications can even change the pH of your soil. I use a product at work that is a total of 12% humates. It is 9% humid acid and 3% fulvic acid. On three that we injected this along with nutrients and root stimulates, our soil samples have started to show a stabilization of the soil pH without the need to add lime any more. Also the ENR valve of soil has increased 3 fold. Also our CEC s have increased. I live in GA, so heavy clay soil that is typically acidic. I say all of this to say I do use both a humate product and the root stimulant product on my bonsai. As far as soil components, that is always a typical that is hard for everyone to agree on. I have personally started to follow Ryan’s guidelines more and have seen an improvement on my trees. For trees in early development stages I just up my fertilizer and supplements. I am lucky as I can get my hands on products that are not sold to the general public. I plan to play around with a different source of nitrogen this year on a couple of trees, I use it in our turf program now. It is a polymer based product that can feed over a 12-16 week period. It has a carbon to nitrogen ratio of 1:1 just like an organic. It is also 70% water insoluble.


Thank you everyone for your discussions on this. I’m a beginner so I was kinda looking at Dr. Earth root growth stimulate as an option.