Developing Pre bonsai and bonsai soil mix for South Florida

Baku1875

Shohin
Messages
414
Reaction score
590
Location
Southeast Florida
USDA Zone
10b
Hello everyone,

I'm getting ready to repot some stuff, and also hunting for more nursery cans with 'malleable' pre-bonsai material. The heavy rain pattern here, and the root rot casualties over the years has me rethinking my pre-bonsai/development mix (I had been using bonsai jack universal for my 'nicer' plants, but $$$ costly for larger pots). I have a bit of conifer fever and found a local nursery that has some nice Carolina sapphire cypress, arborvitae/thuja, in big pots that could have potential.

I plan on moving away from using any organic potting soil/dirt or canadian peat/sphagnum at all, and going full inorganic. Thanks to this forum, I discovered Safe T sorb and have a 50lb bag coming, and I have also become a full time 'sifter' lol. (with n95 mask and goggles with a fan on at all times...i dont want glass lung)

I have been sifting this 'Gantessa Pumice' that I found on Amazon for a little over 20 bucks for 8 quarts, almost done working thru it, refined it down to two grades- big chunky (>3mm) and smaller pebbles that roughly match the size of the bonsai jack clay pebbles and akadama that I used to buy for my nicer plants. Now that I am a lot crazier about bonsai work, I have tons of plants in development, tons more repottings to come....and I am not interested in more root rot casualties because of poor drainage potting soil.

The pumice is kind of light, but after sifting and rinsing, it's dust free and the 8 quarts yielded plenty of usable material. I plan on using the bigger chunks for developing pre bonsai in conjunction with the coarser sift that I will get from the Safe T sorb, and the smaller more uniform particles will be reserved for stuff that goes into bonsai pots, or cuttings that are in early development.

For this heavy heavy rain environment, would a 50/50 coarse pumice and coarse safe t sorb mix do the trick? I work from home so I routinely check the moisture levels on my plants and water if needed, especially if we have scorching conditions between the rainfall. What kind of fertilizers are practical for using this kind of mix? I know the addition of something like pine bark chunks (trying to find something that comes in similar size to the pumice and safe t sorb particle size that I have) would help with CEC and fertilizer efficacy, but I'm hesitant to add organics because I am trying to avoid killing my conifers with swampy soil conditions.

I hear a lot of positive things about using 1/3 or 1/4 lava rock as part of the mix for South Florida bonsai growing, but I havent found a good 'non bonsai' source that has good yield for the $$. Any input is greatly appreciated!
 

jeffapana

Sapling
Messages
32
Reaction score
104
Location
fort lauderdale
USDA Zone
10b
Bushel Stop used to carry 1/4 inch red lava for a reasonable price. Last time I was there it was much larger than 1/4 inch though, but I don't know if that was because of a new supplier or the employee looking in the wrong pile...
 

Baku1875

Shohin
Messages
414
Reaction score
590
Location
Southeast Florida
USDA Zone
10b
Good looking out, what I meant by 1/3 and 1/4 is that 1/3 or 1/4 of the total mix as lavarock, ie- 1/3 calcinated clay, 1/3 pumice, 1/3 lavarock. I will check them out, thanks!!
Bushel Stop used to carry 1/4 inch red lava for a reasonable price. Last time I was there it was much larger than 1/4 inch though, but I don't know if that was because of a new supplier or the employee looking in the wrong pile...
 

nuttiest

Omono
Messages
1,029
Reaction score
797
Location
fl
USDA Zone
10
I got paver base last month and different bags were both very different than in the past, the limestone pieces are same sized and look like a perfect medium no sifting just rinse. I want to put a juniper in this and try it.
I am on the west coast, there are no rural stores here, but I would love to get chicken grit granite again. The granite kept mosquito larvae out of water buckets last year.
Big bags of lump charcoal from grocery store - just lay them on the driveway and drive over a couple of days, any large lumps left will easy crush with pliers :)
 

penumbra

Imperial Masterpiece
Messages
9,379
Reaction score
15,844
Location
Front Royal, VA
USDA Zone
6
Big bags of lump charcoal from grocery store - just lay them on the driveway and drive over a couple of days, any large lumps left will easy crush with pliers :)
Unless things have changed, charcoal briquettes from the grocery store have chemicals in them to produce an even burn. I understood these to be unsuitable for plants.
 

nuttiest

Omono
Messages
1,029
Reaction score
797
Location
fl
USDA Zone
10
Unless things have changed, charcoal briquettes from the grocery store have chemicals in them to produce an even burn. I understood these to be unsuitable for plants.
No, lump charcoal is totally different than briquettes.
 

Colorado

Masterpiece
Messages
3,104
Reaction score
8,228
Location
Golden, Colorado
USDA Zone
5b
Hello everyone,

I'm getting ready to repot some stuff, and also hunting for more nursery cans with 'malleable' pre-bonsai material. The heavy rain pattern here, and the root rot casualties over the years has me rethinking my pre-bonsai/development mix (I had been using bonsai jack universal for my 'nicer' plants, but $$$ costly for larger pots). I have a bit of conifer fever and found a local nursery that has some nice Carolina sapphire cypress, arborvitae/thuja, in big pots that could have potential.

I plan on moving away from using any organic potting soil/dirt or canadian peat/sphagnum at all, and going full inorganic. Thanks to this forum, I discovered Safe T sorb and have a 50lb bag coming, and I have also become a full time 'sifter' lol. (with n95 mask and goggles with a fan on at all times...i dont want glass lung)

I have been sifting this 'Gantessa Pumice' that I found on Amazon for a little over 20 bucks for 8 quarts, almost done working thru it, refined it down to two grades- big chunky (>3mm) and smaller pebbles that roughly match the size of the bonsai jack clay pebbles and akadama that I used to buy for my nicer plants. Now that I am a lot crazier about bonsai work, I have tons of plants in development, tons more repottings to come....and I am not interested in more root rot casualties because of poor drainage potting soil.

The pumice is kind of light, but after sifting and rinsing, it's dust free and the 8 quarts yielded plenty of usable material. I plan on using the bigger chunks for developing pre bonsai in conjunction with the coarser sift that I will get from the Safe T sorb, and the smaller more uniform particles will be reserved for stuff that goes into bonsai pots, or cuttings that are in early development.

For this heavy heavy rain environment, would a 50/50 coarse pumice and coarse safe t sorb mix do the trick? I work from home so I routinely check the moisture levels on my plants and water if needed, especially if we have scorching conditions between the rainfall. What kind of fertilizers are practical for using this kind of mix? I know the addition of something like pine bark chunks (trying to find something that comes in similar size to the pumice and safe t sorb particle size that I have) would help with CEC and fertilizer efficacy, but I'm hesitant to add organics because I am trying to avoid killing my conifers with swampy soil conditions.

I hear a lot of positive things about using 1/3 or 1/4 lava rock as part of the mix for South Florida bonsai growing, but I havent found a good 'non bonsai' source that has good yield for the $$. Any input is greatly appreciated!

Rather than add an organic soil complement, I use organic fertilizers. Works great for me. I use Biogold pellets and Neptune’s Harvest Fish and Seaweed liquid. Plenty of other good organic options out there also.
 

Baku1875

Shohin
Messages
414
Reaction score
590
Location
Southeast Florida
USDA Zone
10b
Have heard really good things about biogold, didn't know it was a slow release organic. Does it produce any issues with mold or attracting pests during frequent rains?

I have been misting almost all of my plants in a light concentration of neem oil after once they dry up after heavy downpours and it has helped a lot. Several of my deciduous plants get blight and have to chug through it with raw growth and health until the pest infestation/infection subsides. Stuff gets nasty down here.
 

Leo in N E Illinois

The Professor
Messages
11,337
Reaction score
23,254
Location
on the IL-WI border, a mile from ''da Lake''
USDA Zone
5b
Pumice is a great media, one of the few I have used as a sole components medium. I would not use any clay based products if you are avoiding rots.

Pumice, or pumice and lava, and you won't have trouble with rots. Organic fertilizer as you suggested.

Charcoal, as in lump charcoal is fine, helps with mycorrhizae. Only need a small amount, maybe 10% by volume.
 

Baku1875

Shohin
Messages
414
Reaction score
590
Location
Southeast Florida
USDA Zone
10b
I think i am onto something now, I really appreciate the input everyone. Gonna try to get my hands on some 1/4 inch - 3/8 inch lava rock give or take so it blends well with my pumice and safe t sorb particle sizes, and a little bit of charcoal in the mix, and biogold for time release fertilizer and see how it goes for the rest of the season. 30% lava, 30% pumice, 30% coarse safe t sorb (thoroughly sifted of course), and 10% charcoal to help with the rot and encourage good flora in the mix.
Pumice is a great media, one of the few I have used as a sole components medium. I would not use any clay based products if you are avoiding rots.

Pumice, or pumice and lava, and you won't have trouble with rots. Organic fertilizer as you suggested.

Charcoal, as in lump charcoal is fine, helps with mycorrhizae. Only need a small amount, maybe 10% by volume.



This will be my first repot from nursery can to bonsai pot/inorganic mix of the season(August if everything goes as planned), muh bucida spinosa. Got a 12x8x3 inch bonsai pot for it, once it settles in after a few months i'll be chopping the top off and bending one of the upper 'flaps' towards the top to make it the new apex. It has been enjoying the rain and heat this summer.
IMG_4270.JPG
 

Baku1875

Shohin
Messages
414
Reaction score
590
Location
Southeast Florida
USDA Zone
10b
I'll likely dial down the clay/safe t sorb component on the more moisture 'hating' conifers and such and make up for it with more pumice and lava. Bucidas like being moist so I figure it would benefit from some clay
 
Top Bottom