What type of rock dust is best?
Feeding poor soil with mixed rock dust may be compared to feeding an ill person a varied diet of unrefined, natural food. If no one single food is a panacea, it might follow that no single rock type is "ideal." Indeed, the virtue of glacial gravel is said to lie in its broad spectrum of rock types. The late John Hamaker advocated the use of glacial gravel dust, ideally followed by river and seashore gravels and mixtures of single rock types.In the book The Survival of Civilization, John Hamaker suggests finely-ground glacial gravel because that is nature's way throughout millennia to create fertile soils. Glacial gravel, which is a natural mixture of rocks, will create a broad spectrum of minerals in the soil in a natural balance.
Much of value can also be gleaned from Europe and the research and experiences there where single rock types and combinations of single rock types such as basalt are used.
Hamaker asserts that "Micro-organisms select what they need to make the compounds of life, and reject to the subsoil what is not needed, [such as] aluminum, silicon, iron, etc., which are generally in excess [in gravel dust]," further pointing to "the Kervran research on biological transmutations", which suggests that biological organisms may play an active role not only in selecting specific elements, but also in modulating their elemental nature to create needed materials where they are in short supply. Hamaker says "As long as the soil is neutral [in pH] or close to it, microorganisms will control what goes into the plant roots. These controls are off when the soil is acid or acidic chemicals are added."
Composting with rock dust
Combining gravel dust with organic materials in compost is a great way to solve application problems and speed up the process. Don't forget a handful of soil to inoculate with organisms. Gravel dust improves aeration and structure and therefore prevents rotting. Gravel dust is assimilated even more quickly in compost than in poor soils.Compost and gravel dust are a symbiotic combination: the compost provides an excellent medium for the "microorganism population explosion" promoted by the dust, and the gravel dust will not only help create more organic matter, but will also help hold it in place, reduce odors and conserve it.
Add 2-20 lb. of rock dust per cubic yard of compost, if one is doing pile or windrow composting.
Soil acidity
Soil pH should be measured annually. If the soil is acidic,
agricultural limestone may be added together with the rock dust to bring
the soil pH to neutral. Gravel dust will also neutralize soils to a
great degree, but limestone is a quick remedy for agricultural soils.
Limestone is not recommended for forests as it will destroy the
humus-building complex in the long term.Keep insects in natural balance in your garden
For short-term rescue, very fine dust sprayed directly on plants and trees has been shown in research in Germany to deter insect infestations very effectively. Trails of rock dust around the garden help keep slugs out. And healthy remineralized plants will not be plagued by insect infestations in the future as they become healthier and more insect resistant.http://remineralize.org/a-rock-dust-primer
