Anyone have advice on building "raised bonsai-beds"? Want to approximate in-ground growth for some specimen and figured this would be a good approach

[SU2]

Hi BN!!

I'm hoping for advice on the idea itself, and on specifics (IE setups, #'s & ratios etc) of a good setup of this nature. My goal/idea here is to avoid using my over-sized styrofoam coolers for some of my "must-grow a lot, quickly!" specimen by setting-up a "ground-grow area" in my yard, I can dedicate the space/lumber/time necessary to do this properly and am hoping for advice on what a good approach would be, I guess I'm picturing something like an 8' long, 4' wide setup (maybe 2' tall? Would probably have it raised over the ground IE not true ground-growing, unsure if that's dumb or not), and inside that setup I'd have 'dividers' for the various specimen that'd go in!)

Thanks a ton for any advice on this! I'm unsure what I'll be using for aggregate(s) yet, may even be varied because I intend to put my 2 BC's in there (and any BC's I get this season!) so will be setting-up in a way wherein the dividers are quasi-movable and each 'space' is separated enough from any other (IE if I had an 8'x4' setup I could do (8) 2'x2' foot-print squares in it IE each would be 8 cubic feet of substrate), the BC's will probably get a sea-shell + peat mixture, and scoria/perlite/DE for the rest (my usual mix for tropicals!)

Again thanks a ton for any input on this one

[edited-to-add: am I being foolish in not just having this sit on-ground / letting the roots run-out into the ground? I guess my thinking is that, since the box will be running alongside a patch of trees/"woods", that there's so much bug/pest risk from that area that I'd rather just deal w/ canopy pests and not run the risk of nematodes/etc, it's a pretty crummy area that it'll be beside and while I'm going to clean it the reality is it's been a yard-waste dumping-ground, not a compost-pile like it should've been, so when I clean it up it's not some 'homeostatic biosphere' it'll be a chaotic re-build of the area's biome and in those pre-homeostatic states I know things can be risky!]

 

[Bonsai Nut]

It is usually better to go with the "on the ground" approach - unless there is a drainage problem. Knowing the soil in the Tampa area to be in a general state of saturated to REALLY saturated... does the area get good drainage?

 

[Anthony]

Get some concrete blocks and just rest them on each other
like the image. You don't have to cement.
Run rods through if you like.

Approximately 1 foot deep - 1 foot wide and 10 feet long.
But you may not need to be so long.

We also use a colander for convenience.
Can easily be removed and left for some weeks
to re-grow fine feeder roots and then thick roots removed easily.
Good Day
Anthony

Just rest the concrete blocks to get this shape and leave open to
the earth,

 

[clive bennett]

I have grown several trees in my garden, just in garden soil with extra grit, growth is great very fast from year 2 onwards (UK garden) but the roots are terrible and all the prunung and work required to make them usable for bonsai pots takes years. By all means grown in the ground but sort the roots first and plant over a tile to force them horizontal. I now always start them of in shallow pots and do 2 years root training prior to planting out , its faster in the long run

 

[River's Edge]

Hi BN!!

I'm hoping for advice on the idea itself, and on specifics (IE setups, #'s & ratios etc) of a good setup of this nature. My goal/idea here is to avoid using my over-sized styrofoam coolers for some of my "must-grow a lot, quickly!" specimen by setting-up a "ground-grow area" in my yard, I can dedicate the space/lumber/time necessary to do this properly and am hoping for advice on what a good approach would be, I guess I'm picturing something like an 8' long, 4' wide setup (maybe 2' tall? Would probably have it raised over the ground IE not true ground-growing, unsure if that's dumb or not), and inside that setup I'd have 'dividers' for the various specimen that'd go in!)

Thanks a ton for any advice on this! I'm unsure what I'll be using for aggregate(s) yet, may even be varied because I intend to put my 2 BC's in there (and any BC's I get this season!) so will be setting-up in a way wherein the dividers are quasi-movable and each 'space' is separated enough from any other (IE if I had an 8'x4' setup I could do (8) 2'x2' foot-print squares in it IE each would be 8 cubic feet of substrate), the BC's will probably get a sea-shell + peat mixture, and scoria/perlite/DE for the rest (my usual mix for tropicals!)

Again thanks a ton for any input on this one

[edited-to-add: am I being foolish in not just having this sit on-ground / letting the roots run-out into the ground? I guess my thinking is that, since the box will be running alongside a patch of trees/"woods", that there's so much bug/pest risk from that area that I'd rather just deal w/ canopy pests and not run the risk of nematodes/etc, it's a pretty crummy area that it'll be beside and while I'm going to clean it the reality is it's been a yard-waste dumping-ground, not a compost-pile like it should've been, so when I clean it up it's not some 'homeostatic biosphere' it'll be a chaotic re-build of the area's biome and in those pre-homeostatic states I know things can be risky!]

Here is one approach. I used wood ties approx 4 by 4 10 foot. Three high, used landscape fabric on the bottom, 1 1/2 inch drainage layer black lava , filled bed with pumice. You can choose your own substrate based on local options and climate needs. As you can see, i often place colandars or pond baskets in these beds for some purposes. However, there is no reason you could not use this setup and plant your trees directly in the bed.