Start a new thread

1 to 17 of 17 replies

Steve 309

My friend has a box of this whitish powder which claims it's powdered volcanic rock.  It's supposed to be used to fix nutrients near the plants, when you add fertiliser on top of it.

I've never heard of this.  Does anyone know what it is, what it does and how it works?

(apologies if this turns up twice - it seemed to be in the talkback section, which it isn't )

Whitish powder ?  Did it come with a rolled up Fiver to snort it thru

Seriously, I've never heard of it so be interested to see what others comment.

Steve 309

Hmmm... no  - if it had we'd be off to Costa Rica or somewhere coz it's a 2kg box!

Ah well.......just a thought

If it is volcanic rock, I'd always been under the impression that it is an inert material.

I imagine Edd or Mike Allen would be the best people to answer this query.  Sorry Steve..........just seemed too good to pass up

Try Wikipedia. It has a short entry on this stuff and it doesn't mention gardening though Thai farming pops up.


Mark 499

I have seen powdered volcanic rock for sale, supposed to add minerals to the soil, B&Q sell it under the Verve brand, some people swear by it.

Steve 309

Just found this

It's a type of clay, apparently, derived from volcanich ash.  Loads of it quarried in USA - so it clearly has an environmental impact.

It seems that you mix it into the top foot of your sandy soil - looks like about a handful per square foot - to increase its water- and nutrient-holding capacity.

They seem keen on it in Oz - Perth has sandy soil like I do.

Anyone used it?


It's also used for clearing wine.

Steve, I have Sandy soil in part of the garden. Perth is a whole new game. They don't call the western Australians sandgropers for no reason. The only grass that will grow is called buffalo grass. I broke a spade trying to dig it up at my friends new house.

Steve 309

The link above is to a TV clip from Perth.

Tried it in my friend's garden (in northern Belgium) yesterday and it seemed to do the trick.  Time will tell if it holds the nutrients & water in, as claimed.  She has very sandy soil, as do I in Liverpool.


Bentonite Clay is a body detox and is also used to clear contaminated/stagnant ponds. It is very miraculous stuff that cleans ponds in an instant but it is also very controversial.

"Bentonite Clay is an effective and powerful healing clay used to treat both 
internal and external maladies. Its greatest power lies in its ability to absorb toxins, impurities, heavy metals and other internal contaminants. When mixed with water, it rapidly swells open like a highly porous sponge. The toxins are drawn in by electrical attraction and are then bound and flushed out of the system."

You can see how these effects would clean a pond.

Steve 309

Yes.  I suspect any finely divided clay would behave in the same way. 

Whence stems the controversy?  The quarries needed for extraction?


Yes. That point is relevant but as the clay is used to clean water contaminated by toxic material like industrial waste. The product has to go somewhere in the end. There are several different types of Bentonite Clay and the FSA has found online bought products contaminated with lead and arsenic. so avoid the following.

"The FSA is advising people not to purchase or consume the following products:

  • Bentonite Clay, sold by
  • Bentonite Clay, sold by
  • Calcium Bentonite Clay, sold by
  • French Green Montmorillonite Clay sold by
  • Premium Calcium Montmorillonite Clay, sold by
  • Edible Earth digestive detoxicant and ionic mineral supplement, sold by and

This is not a definitive list of products or retailers. There may well be other brands, online and shop retailers selling similar products."

If it seems too good to be true, then it probably is!

Steve 309 they're selling off the clay that's been used to absorb (actually, probably aDsorb) toxic heavy metals for us to put on our gardens?  Where we grow food? 

Shurley shome mishtake?  Either that or something needs to be done about it!  Do the Environment Agency know?  Trading Standards?  And if the FSA know about it, why is it still available?!



Think I'll stick to FYM - at least I know where that's been 

Steve 309

LOL Dove


But you have a point!

Sign up or log in to post a reply