evtubbergh
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Make my own bonsai soil

Hi everyone

What do I mix into my own bonsai soil? I have vermiculite, peat moss, compost, topsoil and I will pick up some more perlite soonish. Can I mix food in the mix too? I have bone meal, Talborne seedling food, 2:3:2, and Seagrow (liquid). I also have macadamia shells, pebbles and gravel for planting.

Do I keep up potting my seedlings or do I rather put them in a shallow dish to prevent the roots getting very deep?

We had a charity sale yesterday and one of the things donated was a set of dishes that I really didn't realise were cast iron and enamelled and they would have made perfect bonsai planters! Only by the time I realised they were being purchased. I underpriced them too! So miffed.

tomc
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Re: Make my own bonsai soil

I'm unsure of the South African common use terms. So bear with the American ones I'm used to.

Soil for a tree to live on in a very shallow in temperate zone is (for me), one part sifted pine bark mulch (also called soil conditioner), and one part sifted granite grit. This is sold as poultry scratch and needs little sifting. A common brand name is Grani-Grit.

You don't have much winter and your soil will need to hold more water than mine. You could add up to 1 part coarse sphagnum (or coco-coir) to four parts of of the recipe listed above.

American perlite or vermiculite is baked at very high temperature and breaks down quickly. You will need what our nursery trade calls 'agricultural' grade perlite or vermiculite. it should be heavier and tougher than the fru-fru junk sold to tourists here. This will work as a replacement for granite grit. High fired clay never ever worked for me. After a while you will get tired of killing trees with it too.

Yes this sounds pretty lean on fertilizer. its supposed to. You will fertilize trees with soluble fertilizer at 1/4 the recommended rate, once every two weeks spring summer and fall.

Organic solid fertilizers invite vermin. Don't use it. One squirrel or dog can undo a hundred hours work looking for the good thing to eat, that the scent of organic fertilizer portends. Plus a tree gets most of its food from the mushroom families feeding off of bark mulch, or from disolved fertilizers.
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tomc
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Re: Make my own bonsai soil

evtubbergh wrote:
Do I keep up potting my seedlings or do I rather put them in a shallow dish to prevent the roots getting very deep?
Planting a tree on a paver buried shallowly to make a spreading root system is done.
evtubbergh wrote:We had a charity sale yesterday and one of the things donated was a set of dishes that I really didn't realise were cast iron and enamelled and they would have made perfect bonsai planters! Only by the time I realised they were being purchased. I underpriced them too! So miffed.
In order to live a tree needs a pretty substantial drain. Was this cast iron ware pierced? If not, maybe you didn't miss much.
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evtubbergh
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Re: Make my own bonsai soil

Shew! Ok so we have neither of those ingredients. I can get acid compost, which I know contains some pine bark. I might be able to buy chicken grit although it may not be granite. Come to think of it I already have a very coarse sand that is technically gravel sized but bordering on sand. It is quartz and uniform. Could I use that?

The perlite I get is friable when pressed together but holds up very well in my pots. I have no idea how this compares to what you're talking about as we only have the one producer. I could ask for un-expanded perlite I guess.

The dishes could have been drilled. Ceramic would crack but these were perfect!

tomc
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Re: Make my own bonsai soil

evtubbergh wrote:Shew! Ok so we have neither of those ingredients. I can get acid compost, which I know contains some pine bark. I might be able to buy chicken grit although it may not be granite. Come to think of it I already have a very coarse sand that is technically gravel sized but bordering on sand. It is quartz and uniform. Could I use that?
Coarse sand will work perfectly. Here (coarse sand) usually involves a lot of my sifting to get some. So I'm jealous ;) Also slate-shale is often heat expended for use as cinderblock material. If you have a cinder block mill nearby it too might be a place to look for material.

Um do you ever have landscape or other outfits that grind brush up into chips? Those will work too.
evtubbergh wrote:The dishes could have been drilled. Ceramic would crack but these were perfect!
Bear in mind I am no kind of ceramics expert, But folks who do claim to be have often said many shallow plates pans and bowls were drilled years (centuries?) ago and converted to bonsai pots, so you will be in good company.
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tomc
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Re: Make my own bonsai soil

Long ago when my daughter first saw bonsai soil, she described it as "A bag gravel with a few bark chips drug through it".

Your enemy to successful bonsai soil is tiny particles (dust). The potting composts that will make a tomato flourish, can drown a tree.
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evtubbergh
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Re: Make my own bonsai soil

Ok, so I am going to make 'soil' out of my gravel as a base. Most river sand has a pile of fines in it but we also get this stuff form one company that is super-sorted and washed. It's weird actually but I have whole bucket of it because after I bought it I realised I couldn't use it as sand!

I can get bluegum wood chips from my cousin who composts it on his farm where he grows trees. The bluegums are an invasive species so he cuts them down and uses them to grow indigenous trees ;)

Can I add a little peat moss to hold moisture in between (without drowning the trees of course)? Or could I use vermiculite to hold some moisture?

Can I add a little bone meal or should I avoid that completely? Bear in mind this is for a new seedling and would decompose long before the tree is even vaguely big enough.

tomc
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Re: Make my own bonsai soil

Put your bark inna barrel and let it pickle. Mycoriza (sp?) will invade and start the slow proccess of decay. Three months is probably long enough, a year is not too much. Don't add water, just let it sit.

I don't know what kind of varmints south africa has, but here in the USofA many of them follow their nose to decay and into and onto your tree babies in pots. Once found by scent they dig heck out of trees and soil looking for the good stuff they are sure is buried in those pots. One has to find a row of azalea chewed into match sticks once to swear off of critter attractants.

I will never (again) use compost made of kitchen scraps or meat by-products in my tree babies. A mole will dig a half ton of bonsai soil to find a single worm...

I use only osmocoat time release pellets and soluble fertilizers like miracle grow.

No bone meal, no blood meal, no kelp.
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evtubbergh
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Re: Make my own bonsai soil

Thanks. I plan on taking the chips that have been sitting for while and are already black. He composts them so I can pick which ones I want at which stage.

The only varmint we have is called Whicky and she loves to follow me around eating fertiliser and bone meal and I have to say she likes to destroy various crops while hunting geckos but she also know that if she bothers my baby trees she won't live to see her next meal. So I would say that should not be a problem. So can I use fertilisers in the sold then?

tomc
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Re: Make my own bonsai soil

I use scentless time-release and soluble fertilizers.

Mm I've seen film footage of honey badgers. I think you could have other nighttime nosey poop eating visitors.
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evtubbergh
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Location: South Africa

Re: Make my own bonsai soil

Haha, we REALLy don't have wild animals here. We live smack in the middle of suburban Johannesburg and in a complex with small gardens and even smaller courtyards.

We get frogs, rats and crabs in our house when the river floods but that is about it. Things are too scared to come in our garden with my dogs generally. The only things are birds that feel safe higher up.

I would worry about rats but since we got Whisky I haven't seen any evidence of rats either. She would kill anything like that that dared come in and sine it is so small it's not much work for her.

If I lived in Nelspruit or out on the edge of the city I would expect things to come in, but not here.

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