AusBonsai

G'day all, does anyone who uses Diatomite, find that it goes green thru to black after a period of time ?? Mine does.
James

A number of people have been reporting it on different forums James, but they don't seem to be too worried about it. Are you using it 100%?

Because it is a mineral product and holds so much water, I guess algal growth could be expected. If Diatomite came in a sheet, it'd be great for growing moss on!

I'm still not convinced about using it 100%, I prefer to use it at 50/50 with potting mix - and so far, no I haven't had a problem with it discolouring.

I have found that too.
Also happens on Kanuma, and only a little on Akadama. I have also seen it on pots with "normal Soil", but as it is black then you just do not notice it

I think it from using Organic ferts mainly, as if I put a few lumps of Dynamic lifter on, then a few weeks later it appears quite thickly.
I find it is not much a problem unless you let i build up to film which can become impervious. I just rake the surface to stop it forming every few weeks, or more recelty have been giving the green a light spray with water / Vinegar

Seems to dry it out and stops mor forming, but have only tried it so far on 2 trees only

Ken

[quote="Tman"]A number of people have been reporting it on different forums James, but they don't seem to be too worried about it. Are you using it 100%?

G'day Taffy, no not 100% I usually mix it with cocoa peat and potting mix.
James

[quote="kcpoole"]I have found that too.

Thanks Ken
James

I've found it happens with mine too. I use about a 80/20 mix diatomite to organic although I'm going to start using it 100%

I suspect that the appearance of this growth is more likely to be a reaction to nitrates on the surface more than the actual substrate composition.

I have found that Osmocote can cause the green slimy stuff on the soil surface when used with high % diatomite mixes. The moisture retentive diatomite seems to break Osmocote pellets down quite quickly.

Cheers,
Mojo

Try adding some horticultural charcoal.

Joel

Thanks for all your info guys, appreciate it.
James