Fly ash as potting mix

[dansai]

Has anyone used fly ash for bonsai mix. My dad got some for fill in a size of 10-20mm and although it would need sifting it is only $15 a meter. Any experience anyone.

[AshBrown]

I use 10mm drainage ash (fly ash) product from the power stations added to our potting mix for a variety of bonsai stock(mostly pines and a couple of conifers) and have been doing so for a few years now. It gives a better drainage and far more oxygen in soil mix ie less chance of rot from extended wet periods.

I have found it does require slightly more waterings than regular potting mix. I have fewer "rejected" plants and near zero death rates on a bed of 1000 black pine seedlings in first twelve months. With our regular potting mix i would always have a few.

I hope this helps
Ashley

[Bush bunny]

What is Fly Ash? I sprinkle wood ash and charcoal onto of my pots? It seems to invigorate some plants.

Sorry to be such a twit?

Bush Bunny

[AshBrown]

It is a by-product of powers stations. It goes by fly ash or drainage ash. It can be from a few mm to about 40mm. Hard very irregular shaped lightweight material. Picture attached hopefully.

[dansai]

This stuff is sourced from a local power station and mixed with the yard scrapings(lanscape yard- all the spilled product, dirt, sand and rock) to make a cheap fill. It appears similar to pumice and i assume would hold some water. A lot cheaper than diatomite but was wondering how it would preform as a major component. I'm on my phone at the moment so will do some more research when I return home tomorrow.

[dansai]

Apparently not so good for crysathanthium or turf grass, but good for tomatoes.
http://www.flyash.info/2005/206cho.pdf

[Neli]

I have used it for 25 years in a commercial nursery. I used to add it to improve drainage, absorb water and release it when needed, but in small quantities added to the potting mix.
Before deciding to use it for bonsai I decided to check the PH....it was 14...So I was scared to use it. Tried to put it in acid bath to neutralize it....but it still leaches alcaline.
We call it clinker here...it is a product from burning coal in kilns.

[dansai]

Thanks Neli. The pH was something I was worried about too.