3 cf Edna's Best Potting Soil
.5 cf Perlite
.25 cf Edna's Best Compost
.25 cf Agrowinn EWC
= 4 cf of soil
2 parts Agrowinn Minerals
1 part Oyster Shell Powder
1 part Soft Rock Phosphate
1 part Sul-Po-Mag
= 6 cups of mix (1.5 cups/cf)
.25 tsp/gallon Bioag TM-7 Humic Acid
You would be hard-pressed to find a better EWC product than the one that you've chosen. It's probably the best commercial one on the West Coast. If it were me and money wasn't a huge consideration, I would forego the Edna's Best Compost and bump up the Agrowinn EWC product to 1 c.f. which will give you about 25% of a very strong humus profile.
Better yet would be to use 2x of Edna's Potting Soil, 1x Edna's Compost, 1x Agrowinn EWC and 1x perlite/pumice/rice hulls - whatever you opt for. That would be the best use of the products that you're able to source, IMHO
I would suggest reducing the Agrowinn Minerals back to 1 part and replace with 2 parts of glacial rock dust. Only. Glacial rock dust does not contain aluminum (written as A++++) as do the broad spectrum mineral complexes (sometimes called collidial or nano minerals)
The colloidal minerals used in nearly all mineral products are derived from clays that have origin of volcanic activity from deep within the earth. These clays vary slightly in their composition and therefore are called different names like, bentonite, montmorillite, kaolanite, pyrophillite, and zeolite among others. Collectively they are known as alumino-silicates
, a sub-class of phyllites.
The commercial product Azomite is a montmorillite clay for example. Some minerals in these clays are not found in small portions: such as aluminum (which may be obvious from their common class name). Typically, aluminum constitutes about 10-20% of these clays.
On the oyster shell powder vs. K-Mag, I would suggest going with 1.5 parts oyster shell powder and 2 parts K-Mag to reduplicate the calcium/magnesium levels found in healthy plants.
It's important to remember that top-quality earthworm castings have very high levels of both Calcium Carbonate (the calcium is 'carbonate-d' in a worm's digestive tract) and Magnesium - again in the proper balance. You basically want a ratio of 5 - 8x calcium carbonate to 1x magnesium. Plus you have strong Ca profiles in the kelp, alfalfa meal and fish bone meal as well - all in forms easily chelated and released by the soil's bacteria and exuded for the adsorbtion of its cations to the soil organic matter (SOM) and clay components in your soil mix.
The application of AACT is to mend or repair substandard soils out there in the real world. And not much is used either - like 5 gallons diluted to 50 gallons and that's the amount applied to an entire acre - an acre. Brewing 5 gallons and applying to an indoor garden is an interesting concept to say the least.
With a humus source like you're planning on using a single application and letting the soil sit for a few weeks would be about all you would need. Seriously.
P.S. - regarding CeC, one thing that is important to remember is that the 4 primary cations that create soil health are Calcium (Ca++), Magnesium (Mg+), Potassium (K+) and Sodium (Na+) and all of these are alkaline. The other 2 cations found in soil which can influence pH are hydrogen (H+) and aluminum (A++++) - both of these are base acids and do not contribute anything directly to a plant but are necessary to consider when using mineral mixes.
Or something like that.......................
Edited by LumperDawgz, 22 August 2010 - 07:31 PM.