Another way of extracting money out of people for something they probably don't need. If you think your soil is "depleted by centuries of chemical fertilisers", test it and then add anything that is deficient, in powdered rock form if you wish. Quarrying rocks and transporting them around the country to add to soils that don't need them is not ecologically friendly or good for climate change despite the claims for this product. Shouldn't harm your soil though, just your bank balance :)

Half a century of chemicals, not centuries.

I have no idea whether my soil is depleted by over-use of chemical fertiliser as the second occupant of this property, who lived here for sixty years or so, and was apparently an enthusiastic gardener, died in 1999. He might have been a keen composter, he might not. What I do know is that his successors imported a load of topsoil to create a new border, filled it with plants and then did nothing for six years. I have incorporated loads of well-rotted manure and will continue to do so, but that may not be enough, I don't know. Some of the plants suffered last summer but then it was very dry and they are all pretty young. Because I garden organically and we have a problem with foxes (so no blood/fish/bone), there is not much available to us in the way of fertilisers. An obvious alternative is seaweed meal (or calcified seaweed but I am concerned that it might raise my soil pH).

As for soil-testing, well, it is likely to cost more money to test my soil for trace elements - which would involve sending off a sample to a lab, as the kits you buy from the garden centre don't cover these - than buying a few bags of Rockdust or seaweed meal, and if the soil test told me that I needed to add trace elements, then I would still have the expense of buying the powdered rock.

So the advertising is working then ;) You're not sure, better add some just in case? Please don't, 90% chance your soil is healthy and balanced.

If a soil test tells you to add something, I would strongly recommend you don't add some expensive product that won't even tell you what it contains. Do you even know if it is is alkaline or acid? Here's a quote for you: "it contains a natural balance of lime", how can they know what is a healthy balance of lime without knowing what your soil is like? Its not even truly organic (in the sense of being sustainable), its mined! Here's another quote for you: "SEER Rockdust is freshly crushed volcanic rock from Collace Quarry in Perthshire, Scotland." Please don't be taken in by their frequent mention of the word "organic", because they aren't. Basalt is allowed by the Soil Association only by written permission and with a special justification.

The one thing that rock dust will not supply, and I can guarantee this, is nitrogen. Much maligned by the trendy modern soil fetishists, it is still the single most important nutrient for plants. Your composted manure provides that plus a wide range of minerals and trace elements, in balanced quantities :)

If you really want to go ahead with some powdered rock, and some soils will certainly benefit from added basalt, check for a more local source. Quarried basalt dust is a waste product and is available for around thirty quid a ton delivered, or bagged for about a pound a kilo. The exact chemical makeup of basalt varies with location but expect any basalt to be a mix of calcium, sodium, magnesium, and iron silicates, relatively inert and, if anything, acidic although several remarks on the SEER pages imply that their dust is alkaline.

Read Graham Harvey, "We Want Real Food", about the demineralisatin of soils and the consequential harmful effects on human health. Scary.

I haven't read this book, but the evidence that the average life expectancy in the UK keeps going up and up tends to discourage me from believing that there is any real problem with our food. If there was, I would be more inclined to attribute it to use of chemicals or poor dietary choices than to soil quality.

Chill, chill. Gardening's supposed to be a relaxing, pleasurable hobby. It doesn't matter if it's not perfect. You don't have to change the world one garden at a time, though every little bit helps, I guess. It would help the most if everyone just used home-made compost on their gardens and grew what was willing to grow in it. Which is usually most things.

i believe that rock dust can help you improve the quality of you soil BUT and its a big but, only if you have been intensivly farming your land for 50 years using artificial ferts without incorperating any organic matter it would be helpful. what about the use of sub-soil in small quantities that should have the same effect? i am trying it on my allotment this year i will let you know how it goes

I suspect Steve is right and that Rockdust is more relevant for farmers than for home gardeners.

On the other hand, if home-made compost has not ever been added back to our garden - and I have no reason to believe that it has - then it would not be surprising if the soil were depleted of nutrients.

And, if the restoration of nutrients reduces the amount of watering I have to do in summer - which has been the experience of the Thomsons - then that would save me a lot of time and trouble (and indeed expense - given that last year I had to buy and run an electric pump to empty the contents of my daughter's paddling pool over my borders to stop the plants from dying).

All in all, I think I will add some seaweed meal and see how I get on with that (plus home-made compost plus well-rotted horse manure).

There is a lot more to this I suspect that simply, re-mineralisation - which implies the basic few gross bulk minerals, Ca~Mg, K~Na, Fe~Zn etc

Here we are talking about a very wide spectrum of minerals and trace elements, in a highly absorbable form.
One such that is known to be deficient in root-crops grown in Norfolk (where many of our carrots come from) is Selenium.

And it isn't just about what the plants want to take-up, its as much about the ability of the soil's micro-organisms to support plant and root growth. The Russians did a lot of research into root chemistry and biology this during the post-war years, not able to afford the massive quantities on NPK style fertilisers being used more & more in the West to retain crop-production.

I also don't think its the deplection of trace elements by use of chemical fertilisers as much as the depletion by repetitive growing of crops that take them out, many now residing deep in cemeteries or long since washed out to sea. It is known that Nitrogen sufficiency is extremely important of course, but far from the sole arbiter of healthy & fully nutritious crops... as evinced by the slow dawning that sufficient protein, carboyhdrate & fat were only a very crude guide to human nutrition.

PS I'd like to know where to get volcanic rock-dust at £30/ton delivered (without buying 30 tons!)

Mr.Hughes has the best proof of the wonders of granite rock dust. Show us your pic's.

Here is a link that might be useful: jonhughes use rock dust, mostly grantie I think