Exposed Root JBP - Soil Too Compact? Watering?

[Grunge_Bonsai]

First post here. Been working with trees for about 3 or 4 years now, so all criticism, whether constructive, destructive, or instructive is welcome.

I recently acquired these JBP from Eric Schraeder’s Bonsaify operation. What drew me is they are being developed to become exposed root trees (all except one). There are three trees in total.

Some pics of the different trees and roots in question.

The question I have is on soil water retention and pines. I am in zone 8B (Georgia) where the temps here in April are already hitting 90 degrees.

These are potted up in a mix of 60% perlite, 30% coco pith (peat), and 10% small grain lava. The mix seems to hold onto water quite a bit, though even in the night air it seems to evaporate some, so the mix seems to stay nearly constantly damp.

I am covering the exposed roots with sphagnum moss to protect them. The have been potted up this way for a few days. Based on pics below, do you think the roots can expand and grow into the substrate? The stuff seems compact, but staying quite damp. Any advice appreciated.

How often to water with a mix like this with pines?

 

[Shibui]

I have not used a coir (coco peat) based potting mix so can't tell you how quick it will dry out. That will be different in each area anyway, even growers nearby will have slightly different conditions.
The best idea is to monitor soil moisture daily until you can get a feel for how it copes with your area. It's likely the coco peat that is holding the most water. 30% seems quite high for peat in potting soil and 10% lava is quite low. Perlite is a good component for soil mix but it is very light and tends to 'float' out of the soil when you water which may make the mix underneath even more peat concentrated.
The pine roots will definitely grow into the new mix provided you can manage to maintain reasonable soil moisture.

I can tell you that the pond baskets tend to dry out way more than any solid wall pots so I'd err on the side of caution and water more than less. Dehydration kills in a matter of hours. Overwatering takes months to kill a tree. Your peat based mix may actually help counteract the pond baskets.

 

[littletreefarmer]

I use a very similar mix, 25% coco and 75% perlite, for all of my trees in development although my climate is very different from yours.

I will say that your biggest threat appears to be how large of a container and soil mass you moved the trees up to. Even though they are pond baskets, the roots of the trees look tiny in comparison. I'm just getting into growing pines from seed myself, so I'm learning this too. Normally increasing the container size that drastically is asking for wetter conditions for a while, but seedlings may grow faster to use that space. I would just monitor the soil conditions a few times a day and try to get a good feel for how the plants are using the water in the containers, and water when almost dry.

 

[Cadillactaste]

... I think you are confused on how exposed root are developed. This will shed light on it for you.

How to create exposed root pine bonsai - Bonsai Tonight

Beginners guide with photos and detailed instructions for starting exposed root pine bonsai from one year-old black pine seedlings.

bonsaitonight.com

 

[Maiden69]

I think @Eric Schrader uses coco coir exclusively on his developing material. After seeing his videos I bought a brick to try it out on my cuttings, but have not used it yet. Seems way better that peat moss and from his videos it cleans easily from the roots upon repotting.

 

[WavyGaby]

Eric uses a 4:1 ratio of perlite to peat so what you have will hold a bit more water. I've tried upping the coco ratio in the past and testing it on pines and junipers. The higher coco ratio caused problems for me because most of my trees are in a highly porous mix that will be watered 2x daily in summer conditions and the high coco pots stayed too wet. It might be ok since GA is really hot and you are growing in net pots. I would keep these in full sun and monitor the soil moisture daily. You might find that you only have to water every other day with this mix, especially into the heat of summer when pines will reduce evapotranspiration.

 

[Srt8madness]

I think @Eric Schrader uses coco coir exclusively on his developing material. After seeing his videos I bought a brick to try it out on my cuttings, but have not used it yet. Seems way better that peat moss and from his videos it cleans easily from the roots upon repotting.

I'm using a coir/perlite mix to grow out my seedlings this year. I was inspired by one of his videos.

 

[Grunge_Bonsai]

... I think you are confused on how exposed root are developed.

This is the way two of the three were developed before they got to to my door. I am going only for a small amount of exposed roots at the base to suggest trunk flare. I may adjust this later with a much later repotting.

 

[Grunge_Bonsai]

It might be ok since GA is really hot and you are growing in net pots. I would keep these in full sun and monitor the soil moisture daily. You might find that you only have to water every other day with this mix, especially into the heat of summer when pines will reduce evapotranspiration.

Thanks! Yeah this is what I am thinking. Although I am not using an above-pot container to develop really long exposed roots, I have them wired down to about 1/3 of the lower roots beneath the surface, with the healthy tips spreading out into the substrate. I am using moss and substrate to stabilize the wired portion of the roots, with some of the wired portion sitting just below the soil line.

I am thinking these can be developed over another year or two without repotting. I appreciate all of the replies! What a fast response from this community. I will dial in the watering, keep an eye on moisture needs as time comes to complete decandling, and report back results.

 

[bwaynef]

I think you're going to have a hard time maintaining enough moisture for those roots to develop. Most exposed roots are developed and THEN revealed. The sphagnum isn't going to maintain enough moisture to keep those roots happy. Plant it deeper for another year and slowly start to expose them.

 

[Grunge_Bonsai]

Plant it deeper for another year and slowly start to expose them.

Hmm think they will die off as they are?

 

[Deep Sea Diver]

Good effort and initiative!

Yep, that was a very slight faux paux in the procedure. Seen it done before. Not to worry. All is fine

• Just take a round container, cottage cheese, 2 L soda pop bottle or the like as desired. Then:
• Cut down to the amount needed to cover the roots. Put a couple small holes 3-4 in the bottom edge
• Remove moss.
• Slip over the tree and roots and screw into the surface of the media.
  Put wires in the bottom holes if needed and fasten mini stakes to drive into the media.
• Fill up with lamedia to the top of the roots.
• Carry on with your project as normal.

In 1-2 years start cutting down the top container say 1/2-1” at a time and expose the upper roots.
Continue doing so until the entire top section is exposed. At that time one might pull the entire tree out, remove the wire, and rewire roots as needed for desired effect.

Good Luck! Love to see updates here.

cheers
DSD sends

 

[Grunge_Bonsai]

Most exposed roots are developed and THEN revealed.

Good effort and initiative!

Yep, that was a very slight faux paux in the procedure. Seen it done before. Not to worry. All is fine

• Just take a round container, cottage cheese, 2 L soda pop bottle or the like as desired. Then:
• Cut down to the amount needed to cover the roots. Put a couple small holes 3-4 in the bottom edge
• Remove moss.
• Slip over the tree and roots and screw into the surface of the media.
  Put wires in the bottom holes if needed and fasten mini stakes to drive into the media.
• Fill up with lamedia to the top of the roots.
• Carry on with your project as normal.

In 1-2 years start cutting down the top container say 1/2-1” at a time and expose the upper roots.
Continue doing so until the entire top section is exposed. At that time one might pull the entire tree out, remove the wire, and rewire roots as needed for desired effect.

Good Luck! Love to see updates here.

cheers
DSD sends

I think this just blew my mind. Yeah good idea - that way I don’t have to disturb the plant again and can give it what it needs to grow, then slow reveal. I think I will use landscaping stakes to secure the upper containers.

Thanks. Will post an update after doing this and seeing them through the growing season.

- Grungey Noob