Diatomaceous Earth

So a pal in the US has recommended that we try diatomaceous earth on the garden as a pest control. We already use poultry grade to keep the girls' coop free of nasties, but I wondered what your thoughts are as my reading has brought up some controversy:

So here's the rub:

Some sites say that Silica, which is in human grade diatom in the UK, is GOOD for you, other sites say you should be avoiding silica.

I am looking at food grade diatom purely because I'd be putting it close to my veggies which will be for human consumption.

i'd be interested in your thoughts, wisdom and experience please.

Cheers

I was doubtful about that, thinking it would just be the same as adding rockdust - but you are quite right Yorkie 

Wikipedia says: Although considered to be relatively low-risk, pesticides containing diatomaceous earth are not exempt from regulation in the United States under the Federal Insecticide, Fungicide, and Rodenticide Act and must be registered with the Environmental Protection Agency.[16]

so it would need an EU license.........
The site owner says

Members sometimes discuss making their own pesticides or uses for commercial products beyond those they are licensed for. Whilst not wishing to stifle free speech, this site does not suggest or condone their illegal use

So, of course, you can do what you like but we wouldn't really want to discuss it here 

Sorry, using it like this

try diatomaceous earth on the garden as a pest control

is not what it is licensed for.

Yorkie has it right

If it is not so licensed, it is illegal to use it for that purpose.

You can buy it quite legally as a health aid!  For human consumption! In the UK!

What is the point here, why use something that is expensive when there are easier and cheaper option's. I also thought that one of the major benefit's of growing your own was that you knew no harmful chemical's had been used. Now we are debating using a chemical that has conflicting report's as to it's safe/legal use. I just don't get it man.

Here in Canada we get both grades of D.E. - food and agri grades. If you do use it, try not to breathe it in as the very fine particles (ancient seashells) can get into your lungs and do damage). It's a very fine white powder best applied on a non-windy day and is safe to apply by bare hand.

That said, they're otherwise a very safe product to use to kill most soft bodied critters and popular with organic growers. Think very fine eggshells. Like anything else, D.E. washes off with rain so must be reapplied soon after. There are no chemical additives with DE, just the finely ground shells. I don't know where people get the idea DE is a chemical. It's NOT! The chicken form might have something added but not the agri form.

Food grade DE, a cleaner grade of DE, is a bit pricer and harder to get as it's for actual consumption for specific health problems. Agri grade is very easily washed off prior to cutting up veg, etc so no worries there about accidentally ingesting it. It's just like washing off dust or dirt before eating your veg/fruit. I've used it for years and am still healthy with no problems, unlike other highly touted insecticides that you need a lot of protective gear to apply.

Hope that's what you're looking for, Arwen.

We use it on our hens too, for pest control, and I've tried if on the aphids too - not sure of the impact to be honest on the green fly, been too wet really.

The thing you really want to avoid is inhalation - warm, moist, sensitive environment with little means of escape. You'd be looking at a similar thing to asbestosis I think. Silica itself is silicon dioxide. As such, you're consuming it already - grains have it, hard water has it, beer has it, bread, etc, etc.

Personally, ( IANAD ) putting DE around your plants wont do you any harm. You might do harm to beneficial insects and you'll have to refresh it after it rains ( if it ever stops that is ).

Best of luck, obv take the above as you find it, no warrently expressly given, etc :-)

Dave