Treatment of used bonsai soil.

[james76110]

I'm considering using diluted lime sulphur (1:30) for treating my used bonsai soil. Has anyone tried this?

 

[Danonito]

what i've seen people do (and I also follow the same practice) is wait till the weather is warm , dry the soil completely in the sun, sift it in sizes and discard the leftover fine material. Provided that the majority of the soil is already inorganic, there is no real need to treat it in my opinion unless its coming from a sick tree, in which case you should just discard it completely to be safe.

 

[Cajunrider]

You can bake it in an oven after sifting it to get rid of fine.

 

[Wires_Guy_wires]

I would not use lime sulfur on soil. It contains too much minerals.
I put my soil out in the rain, then let it dry and sift the dirt out.
Most fungal spores can survive dry heat up to 110°C, and cooking your soil hotter than that might crack the particles.

So I don't re-use soil from sick plants, at all.

 

[Brian Van Fleet]

Nope, I just leave it outside on sieve boxes for a few months and them sift it out and store it in a bucket.

 

[bwaynef]

You might notice that people go to some trouble to keep lime sulphur off of soil when its applied to the rest of the tree. That's probably instructive.

Zerotol is OMRI listed and to my understanding breaks down quickly once applied. Being mostly peroxide, it breaks down to water and oxygen, neither of which are harmful in soils.

 

[Paradox]

You can bake it in an oven after sifting it to get rid of fine.

Id prefer an aluminum pan on a BBQ grill to doing it in my house

 

[WNC Bonsai]

I just treated 2 batches yesterday and have another 3 to do today. Mine is a mix of pumice, Permatil (heat expanded slate) and composted pine bark. I used a large disposable aluminum turkey roaster pan, put in about 3” of used soil, and cooked it on the grill for 30 minutes. Bonsai Jack recommends 30 min at 200 degrees but I couldn't keep my grill below 300 so that’s what I used. After cooling I put it in a clean dry 5 gallon bucket from Lowes. The heat treatment should kill just about anything in the soil and also got rid of all the left over organic matter except for a few large bark chips. So now all I have to do is add back some sifted pine bark and it’s ready for repotting which also began 2 days ago.

 

[Cajunrider]

Id prefer an aluminum pan on a BBQ grill to doing it in my house

I am thinking about using my electric smoker. 225 deg F 12 hours should kill most everything.

 

[AnacortesSteve]

I put my old substrate in a big tub that I use to mix my grow mix, which I don't use in potted bonsai. I then add more pine bark, pumice and composted manure. Remember there are a lot of good fungus in there too and this helps the younger 1 year old to 3 year old trees grow. These are in #3 air pots so I don't worry as much about drainage.

 

[rockm]

Skip the lime sulfur. If you really really want to re-use bonsai soil put relatively dried out soil in a black plastic garbage bag. Leave the bag in the sun all summer--don't open it. shift the soil every couple of weeks. Should be sterile from the heat by the end of the summer.

 

[Tieball]

Skip the lime sulfur. If you really really want to re-use bonsai soil put relatively dried out soil in a black plastic garbage bag. Leave the bag in the sun all summer--don't open it. shift the soil every couple of weeks. Should be sterile from the heat by the end of the summer.

Similar. I put old substrate and soil in unused wooden boxes and cover with a black tarp. I just place the full boxes together and cover with the tarp held down by rocks wherever needed and keep it in a full sun location. Periodically, when I remember, I use a trowel to shift the material around and cover it back up. I usually leave it covered for several weeks as every day isn’t sunny for me. After that it’s open for use.

 

[Deep Sea Diver]

We water wash, heat treat ours and sieve. Batch awaiting heat treatment. Fast and back in action asap.



Cheers
DSD sends