Min

Only seen diatomaceous earth as far as clay like products go. I’ve used dish soap/water in a spray bottle, wipes out aphids in short order.

Ammonia for slugs. Plants like the nitrogen too. 

I stumbled across a product called Surround which has it's ingredients as 95% kaolin and 5% of a proprietary something or other.  It got me reading and it looks like just plain old calcined kaolin and soap would do the same thing. Supposed to confuse the bugs and maybe also act as a barrier in areas of extreme heat. Don't think I'ld want to be downwind when it's being sprayed but maybe less harmful than some of the chemical pesticides, dunno? The amount of rain we are getting lately would wash it all off.

Hi @Min,

I know a biological growing orchard near Quebec City (QC Canada), of which the owners apparently use clay on the fruit trees, apples, pears, etc . I know because they mention it as such.  If you'd like to write to them , this is their e-mail: fermelamarianne@gmail.com