Could these be used as soil for Chinese Elm?

[archer66]

Hello everyone,

Let me get straight to the point. I'm living in Bulgaria and I'm having troubles finding stuff to mix good soil for Chinese Elm, which was gifted to me(as usual the tree for a newbie ). I've read some of the info here and some other articles for soil structure( Harry Harringtons basic guides). I have done some research on what is available as materials for "soil" in my country I would need some advises on what could be used. I do have access to the following materials:

Vermiculite - Manufacturer says it could be used as up to 50% of Bonsai soil
Perlite
Keramzit - This seems to be a material widely used in the former USSR for insulation. Sold for pot drainage. I think its made from baked clay.
Lava Rocks - They look red-brown, small balls 5-10mm I think widely used in hydroponics.
Pine bark - still looking for it
Peat
2 Brands of soil sold as "Bonsai soil":
Brand A - peat, clay particles, sand and crushed keramzite, enriched by basic nutrients and trace elements.(haven't seen an opened bag to know how big particles are).
Brand B - Black peat, sand, clay, lime and nutrients.
Orchid substrate - Natural pine bark, peat and Styromull ( was wondering if this could be used also)

I need to decide what could be used for Chinese Elm particularly, when taking into account my geographical location and the fact that I am living in an apartment with a small western terrace. The new container is 20cm in diameter and 7-7.5cm deep.

Thank you in advance.

[tomc]

Much of my milage goes to New England commercial availability. When I was at my peak I needed about four cubic yards of mixed soil.

There comes a time when buying retail doesn't work. How much my endeavor and yours will overlap I'm not sure.

For stoney inert material:

Oils Dri; supposedly a high fired clay product. Every one I tried melted into glue in a few weeks. if your clay product can not stand up to 30 days immersion in water, its got no chance as bonsai soil.

Sand; This predicates you have the ability to move and sift soil (sized screens). Particles that are too big to pass through a 1/2 inch hardware cloth screen are too big to be bonsai soil. Particles small enough to pass through a 1/16th inch window screen are too small to be used as bonsai soil.

Heat expanded shale, is a product used in cinder-block mills. It is pricey to me and not that commonly available.

Granite grit I; sometimes sold presifted here as scratch for chickens.

Granite grit II; a byproduct of gravel mills. Has a fair amount of fines that need to be sifted out. Cheap by the ton.

Vermiculite or lava rock; both could work fine if sifted first.

Organic Materials
Bark mulch or soil conditioner started out life here as a byproduct of saw mills. When bought by the cubic yard, or ton is fairly cheap but needs too big and too fine particles sifted out (1/2 inch is too big, 1/16th inch is too small). Now a days is often sold by the 50# bag.

[archer66]

Hey tomc, thanks for the advice. Today I visited some markets, but choice was not good at all. I think I will go for Vermiculite as it seems it is the easiest obtainable here mixed with Brand Bonsai soil( that thing looks more like substrate for Cacti ). I saw there was a coniferous Bark mulch and from what I recall it was made from Cedar, not sure if it was composted

The Chinese elm looks really bad. Fine roots are sticking out of its "bonsai"pot and its soil looks just like Harry describes it in the Mallsai tutorial. That's why I'm in a hurry to transplant it.

The Keramzit stuff, which I mentioned, seems to not sink in water. This is bad right ? I will leave some in water tough, to see what happens.

[tomc]

I think I will go for Vermiculite as it seems it is the easiest obtainable here mixed with Brand Bonsai soil( that thing looks more like substrate for Cacti ).

Brent Walston (evergreengardenworks.com) uses vermiculite in his pots (or did last I knew), for the inorganic part of his bonsai soil.

I saw there was a coniferous Bark mulch and from what I recall it was made from Cedar, not sure if it was composted.

It should work, the question isn't how composted it is, rather how sifted it is. If its half or more fines (small enough to pass through a window screen), It will need sifting.

The Chinese elm looks really bad. Fine roots are sticking out of its "bonsai"pot and its soil looks just like Harry describes it in the Mallsai tutorial. That's why I'm in a hurry to transplant it.

This late in the year I'd slip-pot it; (replant into a slightly bigger pot without working roots till next spring)

The Keramzit stuff, which I mentioned, seems to not sink in water. This is bad right ? I will leave some in water tough, to see what happens.

Very light soil amendments like vermiculite or perelite can easily float off (or blow away) if used as a significant part of your soil. They may not break down, but refuse to stay put .

[archer66]

It should work, the question isn't how composted it is, rather how sifted it is. If its half or more fines (small enough to pass through a window screen), It will need sifting.

The particles were looking big(a bag was opened and I was able to see a some were 2-3cm). Guess it was good enough but I will continue my search for coniferous bark in gardening centers.

This late in the year I'd slip-pot it; (replant into a slightly bigger pot without working roots till next spring)

You have just brought a solution to my biggest concerns ( could I transplant it late spring? can I prune roots? should it be a bonsai pot or ordinary plant pot?). I bought a round ordinary pot ~1.5L as I wanted to get some trunk tickness.

Here is a picture of how Vermiculite, Kermizite and "Bonsai soil" sold in my country look like:



It seems that this "Bonsai soil" has some crushed clay particles in it. I am thinking to go for ~30-40% Vermiculite mixed with the ready available soil.

[tomc]

Go with whatcha got. You will still end up watering (and checking watering) to your new soils needs.

Stick a finger in your dirt (or a chopstick), if it damp, hold water. If its dry, water liberally.

[archer66]

Yep, that's what I always do when checking if soil needs watering. It would either be the finger method or the measuring of pot weight(at least this works with all my indoor plants).

It seems that the small bonsai community in my country is widely using Zeolite( clinoptilolite) which seems to be a bit heavier combined with other inorganic materials plus sphagnum moss for water retaining, or Californian worm poo.