Out of interest why do people think it's NOT a good idea to use cat litter

Andy B wrote: Out of interest why do people think it's NOT a good idea to use cat litter

I hinted at it, but I do not have a problem with it. I have quite a few of my young trees in mixtures containing cat litter. It's cheap and it works well for me.
For more my more mature trees, I do not use it, nor for my azaleas (I'm not sure now. I think I do have two of them in a mixture with it).

I'm using a dutch brand of cat litter for most of my trees in development too.

Mariusz from ibuki-shop.com claims (according to a guy I know (so this is very second hand info btw)) that all the 1st grade akadama we're getting from Japan these days is actually their 2nd grade stuff .The Chinese are buying all the good stuff. So we should be looking out for a good, more local, replacement. Pumice, lava, zeolyte and other granulates should be the future.

Anyway, I have some good results with my own bonsai mix which contains about 60% of cat litter.

For more developped trees I'm sticking with mainly pumice with some akadama, lava and zeolyte but for the young ones it's cat litter mixed with lava and zeolyte all the way. (much cheaper and I need a shitload of it )

Look at what Ryan Neil says, look at what Bjorn Bjorhols says. Ramification small leaves best achieved with Akadama. When it is necessary to wash the produce before it can be used there has to be something wrong.

Ryan Neil is also looking for a replacement for akadama...
But then again, so many people, so many different opinions. If I take the same tree to 3 different workshops I get 3 different point of views.
If you don't want to use cat litter don't use it...

Exactly.
I do not use akadama because in an average winter in my locality it breaks down to mush. I do not want to repot my trees every year. (I have already had over 7 freeze-thaw cycles this winter, and the real winter is yet to start).

leatherback wrote: Exactly.
I do not use akadama because in an average winter in my locality it breaks down to mush. I do not want to repot my trees every year. (I have already had over 7 freeze-thaw cycles this winter, and the real winter is yet to start).

Same. I hate the climate here.

At a bonsai exhibition someone giving a workshop said that if your trees are not in Akadama, you're not doing bonsai.
According to Walter Pall, it does not matter what you use, as long as it is a modern substrate

According to Walter Pall:
Akadama "is questionable as a good substrate as it inevitably decomposes, especially when exposed to winter frost. It can become deadly loam in the pot, choking the flow of water and air into the soil. This is especially true for trees which are only rarely repotted, like collected conifers and old bonsai in general"

However, according to others, the decomposing is a good thing:

"Over time, root growth and consistent watering break down akadama particles. As the particles break down and become smaller, their ability to hold water increases. Given enough time, the particles will completely break down until all that is left are tiny pieces of clay.

The breakdown of soil particles is important in the cultivation of bonsai as smaller soil particles promote slower growth. During the refinement stages of bonsai development, slow growth is a primary goal as vigorous shoots can thicken branches and make old trees look young"
Source: bonsaitonight.com/2016/07/15/all-about-akadama/

However, according to the same article, when Akadama continues to break down and the roots start to fill the pot, drainage can be impeded and this will make it hard to keep the tree healthy. Eventually, it must be repotted.

So I guess it depends. For Leatherback, Akadama doesn't work too well. He has had several frost cycles already and his Akadama decomposes fast.
Living in the same small country, but close to the coast, I have not had such frost cycles yet and it is less of a problem for me.

I do have trees (deciduous) in pure Akadama and they are doing fine. My pines are in a mixture, containing Akadama. My young plants and pre-bonsai are in various soils, several of them containing cheap, baked clay pellets *1)

Now, about soil, the person who has great, healthy trees is the one who is right. Walter Pall does have great and healthy trees, but so do others that have a different opinion.

That's why this will be a never ending discussion. It depends on where you are, how you care for your trees (watering, fertilizing), and the trees you have.
Just use what works for you - and that doesn't have to be Akadama.If you use Akadama, make sure you repot in time (but of course you should always repot in time, regardless of what you use).


*1) Aka cat litter

In my country, garden nurseries widely sell fired clay, unsifted ranged from dust, 1mm to 10mm, even one or two 2cm ball of clays. Pure mix drains immediately and on hot day the couple inches of top soil will dried in 24 hours. My mix mainly using this fired clay, sand, compost, and ordinary potting soil depends on tree.

I don't know the chemical composition of antibacterial and anti odor of cat litter, so I stay away from it. Furthermore non-clumping type is rare here.

Akadama and lava rock could rip your pocket in Malaysia.

Interestingly on another website Harry Harrington has an article on this subject.
I am currently using it on some trees in development in a mixture of shells and coarse sand and compost without any issues to date.
I do sieve it first mind.