Senior Member
Posts: 203
Joined: Fri Jun 26, 2009 9:34 pm
Location: Inland Empire,CA

TDB's_how to make or better organic potting soil guide

I thought id share on how to make Top$ organic soilless potting media either from scratch or to help better store bought commercial potting mixes. To me, soil is both an art and a science; only by understanding our soils biology we can truly enjoy the maximum use of are plants.

I have been having wonderful success with a simple soil mixing method, soil recycling and have experimented a little with other soils/ingredients as well. I want to share my methods and help give an idea of how to build healthy potting soil.

The basics
When thinking of or looking to buy, good soil or soilless media, especially for seedlings; Keep in mind that potting soil should be fine and uniform in texture, well aerated and loose, free of insects, disease organisms, weeds and seeds, low in total soluble nutrients and able to hold moister yet drain well.

Some commercial potting soils that fit this description that I have successfully used are:
[url=]black gold organic potting soil[/url],[url=]kelloggs organic premium potting soil[/url],[url=]whitney farms organic potting soil[/url],[url=]E. B stones potting soil[/url] and [url=]pro mix[/url]/[url=]sunshine mix potting soil[/url].

These soils are high in organic matter, neutral or close too in PH, contain some kind of rock mineral/pumice or volcanic matter and are peat/coco coir based, witch is what I prefer when starting seeds indoors or growing in containers.

I find it best to shop for [url=]OMRI[/url] certified products; this stamp of approval helps gardeners like my self choose quality ingredients that are not high in salts, toxic, or diseased/infested.

simple soilless potting mix recipe
To make your own soilless potting media you want to get either or [url=]peat moss[/url]/[url=]coco coir[/url], [url=]perlite[/url]/[url=]vermiculite[/url] or [url=]rice hulls[/url], and any kind of [url=]compost[/url]/ [url=]EWC[/url] or [url=]composted manure[/url]/[url=]guano[/url].
Other ingredients can be used, but this what works for me.

Look for ingredients that are [url=]OMRI certified[/url] and compost/composted manure that is stamped with approval from some [url=]compost certification[/url] program.
Home made compost or vermicompost can be used, but be sure you know what your doing!

by the way the slash (/) means OR

The basic DIY organic soilless mix that I recommend for beginners or as a base for more advance potting mixes is…

4-5 parts peat moss/ coco coir or coco peat mix
3 parts perlite/vermiculite/rice hulls
2-3 parts vermicompost/ mushroom compost/ compost/ or composted manure


note this recipe can be mixed around to suit plants that prefer more compact or loose soils, this basic recipe works for most vegetables/herbs in my garden!

To the above mix add
1-2 TBSP of [url=]dolomite lime[/url] or [url=]oyster shell lime[/url] for every gallon &
2 TBSP of [url=]kelp mea[/url]l/ powdered kelp extract or [url=]green sand[/url] to every gallon as well

You want to mix all ingredients nice and well either in a heavy duty trash bag or rubber maid/storage container.
Having some one to help is always good too!!
my niece :)

Then while mixing, wet (but don’t soak) the dry mix with just plain water or better yet [url=]ACT[/url] or a [url=]liquid fish/[/url][url=]seaweed fertilizer[/url] diluted @ 1 TBSP /gal water.
(you can use 2 TBSP of kelp/molasses or fish meal to the gal as well)

Be sure you mix and stir the media properly and its best to let the soil sit for 1-2 weeks minimum.
(stirring & mixing every other day is recommended)
This will give the microorganisms time to multiply and stabilize the soilless media.
Once 2 weeks have gone by the soilless potting mix should be ready for starting seeds or can easily be amended for older hardier plants.
if starting seeds, a little corn meal or cinnamon added will help with the dreadful damping off fungus

Advance soil mixing for mature or specific plants

If building a soilless media for mature plants or amending commercial store bought soilless media’s, you can easily add other organic amendments before letting the soilless mix sit for a week or two.

I find it best to add only 1-2 TBSP or 1/3 cup of any soil amendment when prepping potting soil.
(unless experience tells you otherwise)
Only add amendments based on knowledge of plants requirements

I prefer to use nitrogen rich [url=]guano[/url],[url=]alfalfa[/url], [url=]blood[/url], [url=]feather[/url] or [url=]fish meal[/url] for N(nitrogen).

[url=]soft rock phosphate[/url], [url=]bone meal[/url] or [url=]phosphorus rich guano[/url] for P(phosphorus ).

& kelp, [url=]green sand[/url], alfalfa, or [url=]peruvian seabird guano[/url] for K(potassium).
keep in mind that all organic amendments listed above do more then add macronutrients

Other amendments like dolomite lime, oyster shell lime, gypsum, and Epson salt are added for cal/mag and to help in ph balance (peat based mix) I recommend 1-2 TBSP of either or.

IMO lightly amending any soil with rock/clay powders or dust (glacial, soft rock phosphate, dolomite, azomite, green sand) helps...alot!
they dramatically increased microorganisms growth, provides a slow balance release of trace minerals, helps build a more diverse soil, increases water holding capacity, and I have noticed a nice increase in crop yield as well.

One thing that I believe makes my potting soils superior is soil inoculants (mainly [url=]AACT[/url], manure or weed tea) & diversity. I love mixing things up with all the amendments I mentioned but the next few im going to list IMO have had the most impact on my potting soils claim to fame.
(it’s the little things that count, microorganisms & trace minerals!!)

[url=]Azomite[/url] - I use this product primarily for its minerals & trace elements, but this stuff has really brought my potting soil alive, I again only add 1-2 TBSP to the gallon but WOW!!

[url=]Glacial rock dust[/url]- again used for its trace minerals, but I find that this product with the diversity of the other rock amendments have really impacted my potting soil

Last but not least

[url=]Diatomaceous Earth[/url]- DE is used in my soil to help prevent any unwanted critters from living or breeding in my soil, a must for soil recycling recipes.

its especially important when adding amendments, to stir, moisten & let the mix sit for a week or two

Well this is it, but for more advance organic gardeners I want to shine some light on soil recycling

Soil recycling~for advance ORGANIC gardeners only

With a fully organic soilless medium I find no reason to go out and buy new potting soil or make a new batch for next years crops. What I have been doing for the last 2 years is a thing called soil recycling.
I learned on how to properly do this by a flock of 3 organic gurus or birds, who really understood organics and easily simplified the whole soil recycling method for many.

So after every container grown crop that dies of old age or has out lived its welcome in my garden. I throw the plants stems, foliage and roots in my compost/vermicompost, then poor the used potting soil in a empty storage container or large rubbermaid.

For every 10 gallons of used potting mix I amend with 1 cup of organic ingredients and 2-3 cups of composted organic matter(compost/vermicompost/mush compost).
The basic recipe goes..

To every 10 gallons of used potting soil add..
1 cup alfalfa meal/blood/fish meal
1 cup bone meal
1 cup kelp meal
1 cup powdered dolomite lime/oyster shell lime
2-3 cups vermicompost/composted manure/compost/mushroom compost

if needed I also add rice hulls/sand/vermiculite/perlite till media feels right &
1 cup of greensand
1 cup of soft rock Phosphate
1 cup of diatomaceous earth
1 cup azomite or glacial rock dust

mix, stir & water (don’t soak) the potting soil in a storage container and again let it sit for 2 weeks minimum. Ther many alternatives to the ingredients listed, these are just ones I have had success with.

With practice/experience youll get a better feel of your soil and plant requirements, in time ingredients added can get mixed around a bit or left out but the end result is the same.
Quality living soil that in my case gets populated with worms from the vermicompost I add. With this method I have actually seen a decrease in insect and disease problems, higher yields (witch makes me proud) and the soil smells, feels and looks great.

Plus I end up saving a lot of money by using less fertilizers and not buying more and more soil, instead my soil goes threw one big cycle very similar to organic matter I add to garden soil.

I insist those who are interested & don’t have much space like my self, to give soil recycling a try & really embrace what organic gardening brings to the table.

(ill slowly be adding to this, but i want to thank A_S & Gnome for helping with codes and HG for help on the soon to come info)
Last edited by top_dollar_bread on Sun Aug 30, 2009 4:57 pm, edited 5 times in total.

Senior Member
Posts: 228
Joined: Wed Jun 03, 2009 6:08 pm
Location: Metro Atlanta, GA (zone 7)

AWESOME POST!!!!!!!!!! Thanks for sharing all this!
Julia in Georgia

Senior Member
Posts: 203
Joined: Fri Jun 26, 2009 9:34 pm
Location: Inland Empire,CA

:D thanx for the kind words
always happy read your generous post, thanks again GeorgiaGirl!

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