[mumofstig]

Rock dust has some wonderful write ups....sposed to be very good for acid soil.

link

I'm thinking of trying some, so, has anybody tried it? Does it work?

[gillie]

To me this looks like a lot of crackpot mumbo jumbo with just a grain of scientific truth in it. 

Rock dust? what rock? assuming it is a calcareous rock it would indeed be good for acid soils - just as lime is.  Some soils may be short of the odd mineral - the trace element selenium springs to mind - so again it would do some good - or you could use seaweed if there was any handy.

Note that this couple growing huge veg mixed their rock dust with 'compost'.

As for making the desert bloom - I don't think so.

Cheers,

Gillie

[Bernard]

It would not be fair to dismiss this too quickly. I think this must refer to igneous rocks which taken in bulk have a rich mixture of minerals, unlike the weathered surface and perhaps all sedimentary rocks. The minerals leach out into the soil, which is why the surface is not so rich and we have to add trace elements. This would be a slow-acting, long term fertilisation. It is not related to liming which is only to adjust the pH of the soil and it does not, of course, reduce the need for organic material.

I used to work in vitreous enamelling and one of our frit suppliers was involved in producing a slow release fertiliser for some desert region. Frit is a granular smelted glass and can have almost any elements incorporated. This is very similar in principle to the idea of powdered rock.

[Trillium]

I found some last year on a clearance and used it. The veg produced VERY well for me and I wished I'd bought more as now I can't find it anywhere.

[mumofstig]

Talking to Aunty i said that if no-one had tried it i would have to be the first! But it seems i will be the 2nd Thanks Trillium will deffo get some now.

[penance]

AFAIK it has been used for quite a while with very good results.