Modloader : Forge 40.1.51
MC Version : 1.18.2
Bonsai Trees 3 : 3.1.0
lib : 2.1.0

I am also using a forge port of sodium called rubidium I don't know if it has anything to do with the custom soil not rendering.

Adding custom soil (in my case I am using Mysticalagriculture farmland) doesn't seem to render:

The json file for the custom soil looks like this:

I'm using kubejs to load it the file path is
[...]\curseforge\minecraft\Instances\justforfun\kubejs\data\bonsaitrees3\recipes\soil\mysticalagriculture

i have some of that problem.
but i notes it in mysticalagriculture soil as other like my oretree soil is working fine.
see here

as for mysticalagriculture soil i change the display soil to block from Minecraft and other mod
see here

here is my file for comparison if you want.

This probably due to some blocks not being simple full sized-blocks or even with custom block entity renderers.
I will investigate and see what I can do.
Probably simply allowing to specify the texture to be used for the soil instead of the block.