80-20 soil mix ? Calling on the experts again :)

[stocaz]

Hi all,

Hopefully this thread hasn't been done to death and I just couldn't find it

Ill be repotting my bonsai's for the first time this year which I'm exited about but as a novice &
With everyone having a different opinion I'm stuck.

I was given a mix of 80% quality potting mix & 20% diatomite to use on my maple,juniper & elms.
Is that ok ?

I was told that it was good by the seller but I thought it needed to be more free flowing.....
I just need some reassurance before I use it on my trees.

Any advice would be great.

Ross

[thoglette]

I was given a mix of 80% quality potting mix & 20% diatomite to use on my maple,juniper & elms.
Is that ok ?

The problem is "quality potting mix". It is a very vague term and few things retailed under that title come close to achieving that.

I like a lot more fired clay or similar (Vermiculite, Zeolite , diatomite) in my mix

[GavinG]

Folk are using up to 50/50 diatomite and sifted potting mix - drains very well, holds moisture well, and has some organic content. You'll still need to fertilise regularly. I'm using 80% water-absorbent grits (diatomite, pumice, zeolite) and 20% coco peat, so you can increase the diatomite quite a lot from 20% and still be in the ball park. Possibly search "soil mix", "diatomite", and so on. If everyone has a different opinion, it's quite likely that all of them aren't all that bad..... You just need to learn what suits your trees, your way of repotting, and your ways of watering. Welcome to the journey.

Are you in a club? If you aren't confident with when different species repot best, personal contact can be useful.

Gavin

[Jasonb]

Sorry if this throws a spanner in the gears stocaz, but I use $3 bags of potting mix from coels and simply add around 20% pumice if I'm feeling fancy, it drains really well, it's cheap and needs no prep. None of my trees have missed a beat.

Jasonb

[lackhand]

Sorry if this throws a spanner in the gears stocaz, but I use $3 bags of potting mix from coels and simply add around 20% pumice if I'm feeling fancy, it drains really well, it's cheap and needs no prep. None of my trees have missed a beat.

Jasonb

And to show the range of possibilities, I grow in 100% diatomite. I used to add coco peat, but I find the diatomite holds plenty of water so it doesn't really need organic material added. I buy my diatomite from the auto parts store at $7 USD for a 40 pound bag (about 18 kilos). As mentioned above, talk to other local growers and see what they use and why as well as when to pot.

In the end, I think a wide range of soil is okay as long as you adjust your watering and fertilizing to match it.

[Pup]

Sorry if this throws a spanner in the gears stocaz, but I use $3 bags of potting mix from coels and simply add around 20% pumice if I'm feeling fancy, it drains really well, it's cheap and needs no prep. None of my trees have missed a beat.

Jasonb

After 12 months how can you tell?? Can we please see some trees?

[craigw60]

There is a new product on the market imported from NZ under the brand name "orchiata" its graded pine bark with a very consistent particle size and almost no fines so sieving and wastage is minimal I have been using that 50/50 with diatomite
I would be very wary of using cheap potting mixes, a close friend of mine came very close to loosing his whole collection after potting them in a cheap mix combined with diatomite, I think saving on potting mix is false economy.
Craigw

[Mojo Moyogi]

There is a new product on the market imported from NZ under the brand name "orchiata" its graded pine bark with a very consistent particle size and almost no fines so sieving and wastage is minimal I have been using that 50/50 with diatomite
I would be very wary of using cheap potting mixes, a close friend of mine came very close to loosing his whole collection after potting them in a cheap mix combined with diatomite, I think saving on potting mix is false economy.
Craigw

Where can you buy orchiata from Craig?

Cheers,
Mojo

[craigw60]

B&T orchids and ferns or garden city plastics
Craig

[hugh grant]

Sorry if this throws a spanner in the gears stocaz, but I use $3 bags of potting mix from coels and simply add around 20% pumice if I'm feeling fancy, it drains really well, it's cheap and needs no prep. None of my trees have missed a beat.

Jasonb

Glad it's going we'll for you mate but a word of advice from someone who used to use coels mix is it will soon turn on you. When I began bonsai I used it because it was cheap and that was all that appealed to me. I later found that after 6 months to a year (depending upon the tree and pot size) the soil became so rock solid it was almost impossible for water and let alone important air to enter the root system prohibiting water and air for the roots to breath. Because it is such a fine mix it drains well initially but after a period of compaction which happens due to root growth and watering it soon becomes and trap for root suffocation!
This is what I found from experience.
Now I'm one of those trendy guys who uses 100% diatomite and a mix of both diatomite an zeolite, works excellent for me.

Hugh

[Brian]

Hugh,
can you elaborate on your mix please ? Have you added organic matter to it ? Are your trees healthy and flush with growth ?

I want to go this way with my bonsai mix. Its possibly the closest to akidama.

[Jasonb]

Pup,

I've been growing plants longer than I've been doing bonsai. And the coels soil hasn't failed me yet. Been using it for a few years now. No compaction other than what I would consider acceptable.

If you want some pictures, what would I post specifically? I would be more than happy to take a few snaps to put up.

Jasonb

[hugh grant]

Hugh,
can you elaborate on your mix please ? Have you added organic matter to it ? Are your trees healthy and flush with growth ?

I want to go this way with my bonsai mix. Its possibly the closest to akidama.

i got into this mix off other people off the forum so there are quite a few other people using it. basically i use diatomite to zeolite in a 3:2 ratio. i sift out dust or wash it out which is probably better so theres no chance of breathing in the stuff. then its graded into large, medium and small sizes through the sieve. in the pot ill layer the mix with largest at the bottom and finest at the top with the finest layer being about 3mm.
for shohin size and smaller trees i use diatomite/zeolite/ sifted ray nesci mix in a ratio of 3/2/2 .
figs, juniper and pine i dont add the fine layer as they like the mix more open and courser.
ive found my trees extremely healthy on this mix and growth has been excellent. although fertilising has to be more frequent it makes for a good excuse to actually DO it

Hugh

[shibui]

all of the above are correct.
Trees are living things and, as such will tolerate a wide range of conditions (including potting mix)
Every grower has different environment and different cultural practices so it is natural that every grower will have a slightly different potting mix to match these differences. Try a mix that sounds right and then try differences until you find the best for YOUR conditions then try to remeber that your mix is 'right' for you under your conditions and not necessarily best for anyone else.
I had one student who managed to keep bonsai alive for many years using garden soil in the pots but I would not recommend that to others, just mention it to show the range of possibilities. she had lerned to match her care regime to the mix and it worked for her at her place.

Are your trees healthy and flush with growth ?

note that what one person considers healthy and flush with growth another will consider poor. These are subjective terms and depend on ones experience and frame of reference (and that is where we get many issues and disagreements).

[Paul W]

Good on you Shibui, trees in the real world grow in dirt don`t they , use whatever works for you,there are heaps of threads on this tired old worn out subject,just use the search facility up the top.