Pro- mix in the white bag?

I’m using Promix from HD big box store. Red bag or yellow bag. I see the You- tube guys getting Promix in a white bag with micro-rhizomes added. It’s too late for this run, but should I try to find the white bag? Is there a difference? I’m adding worm castings, 4-4-4 and power bloom, some kelp meal and crab and lobster meal. I add a bag of washed play sand (11 lbs. I think) to give it better drainage. I’m not a big fan of perlite. It eventually floats to the surface no matter what. I figure that the sand will also add silica and other micro’s. Which one do you use and why?

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You could always add mykos and azos to this mix yourself…I usually do it during transplants even if there is some in the soil.

Thanks, I’m trying to figure out indoor growing techniques. Besides a few house plants every plant I ever grew was outside. I can’t bring my outdoor soil indoors. I get worm dirt (not just castings) that’s loaded with critters. I repotted a plant with it once and brought it in the house. The next day there were no less that 50 flies on the window trying to escape. See if you can find a wholesale bait company near you. They might give you the spent worm dirt. You could offer the a few dollars too. Outdoor use only.

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I would advise to buy a premade soil optimized for Cannabis rather than trying to make your own. Inevitably you will just end up with crappy soil. Promix HP (white bag) has perlite and mykos added to straight peat. This is a ‘soilless’ medium and ought to be used as intended IMO.

Sand will add to the density of your medium and do the opposite of what you want. Perlite and Vermiculite are good and if you want increased drainage raise the ratio of your medium to everything else: it’s designed for drainage.

Now if you want to make your own soil there are recipes here floating around but are pretty complex and expensive.

Here’s the link to his recipe:


Yes I have used it a couple of times. I added more perlite rather than vermiculite and followed the mix formula below. If you wanted higher moisture retention use vermiculite. Normally peat is treated as hydro for ph purposes. Once you add all the other stuff I’m not sure what happens.

This is a mix recommended by Dr. Bruce Bugbee, Utah St Univ in his video Maximizing Cannabis Yields
50% peat (ph of approx 3.8)
50% vermiculite or perlite (brings combination to 4.5 ph)
40g dolomitic lime / cubic foot
10g gypsum (pelletized calcium sulfate) / cubic foot


He favors the vermiculite as it provides Mg. The gypsum delivers the C. So no cal mag needed.

That is a fantastic video and one I recommend as well.


I love watching Dr. Bruce. Very long but detailed. When I need the short version, I watch Debacco University. Average 4 minute watch.
Being new to Indoor growing, I want to keep it very simple for the first few runs. I want to keep the chance for mistakes limited. The less variables the better. Later I can start using liquid nutrients and ph. (ing) the water. I don’t add much to my outside garden other than mulch, sand and some worm dirt. I’ve always found that it breaks up and the clay soil and lets the roots spread. There’s probably not much clay in the potting mix. Indoor mix always gave me problems with repelling water and drying too fast. It would pull away from the sides of the pot. The next time you watered it would run down the sides and out the bottom. Where can I find the promix HP? Does it have the same issues I’m having with other mixes? I’m pretty sure mycorrhizae can be found in my mulch pile.

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Garrigans super soil has definitely got my interest. I’ll have to research where to find cheap but good sources for all those ingredients. I like the Idea of layering the super soil at the bottom of the pot. We did something similar while planting trees.

I use ProMix, either the HP or the BX depending on what they have in stock. I’m not fussy. I don’t add anything to it. Grow in 3 or 4 gallon plastic pots, and I put about 3 inches of lava rock in the bottom for better drainage and air to the roots.
I mix up the ProMix with water with some nutes in it in a big bucket, then add the moistened ProMix to the buckets. Then I do my transplant. Also use the same mix for seedlings or cuttings, bury the small pot in the new bucket, remove it so you have a molded shape of your seedling container, then drop the rooted plant into that molded shape. No transplant shock that way.

Why do I use it this way? Laziness! It’s quick and easy, relatively cheap. I treat it as a neutral soil with nothing in it, everything the plants need, I supply. I’ve heard that some batches of FFOF can be hot, and soils pre-charged with nutrients would leave me wondering how much food is left after a while. I also use Advanced Nutrients pH Perfect line, so I don’t measure pH or PPMs/TDS, I don’t water to run-off, pretty laid-back and lazy approach!

That said, I am getting a pH and TDS pen for Christmas…the Apera pc-60z is what’s on order, but I’m supposed to act surprised when I open it (even tho my daughter got me to order it, lol!).

My ultimate goal is to grow a bunch of varieties to see which ones I like the most. I’m growing autos because they are quick. Also, sticking to the light cycle or fear of light pollution is eliminated. I can start a new variety whenever I have space for it.
Keeping the soil simple and following each light manufacturer’s recommended distances and dimmer settings is working pretty well this time. I have 3 brands of lights and they are all different. A cheap lux meter wasn’t telling me much. There was math to do to determine par value from lux measurements. Math? yuck!

So if I was using a 1.5 gallon pot for veg, I’d use about half a gallon of peat and vermiculite mixed with everything else?

Is this for indoor grows only?..and could it be mixed with a premium soil?

The everything else in Dr Bugbee’s mix is dolomite lime and pelletized gypsum. Both of these are by weight - grams. To end up with a 1.5 gallon of mix add equal amounts of peat and vermiculite (3/4 gallon of each).
Because grams of lime and gypsum are given in cubic feet we need to convert gallons to cubic feet.
1 cubic foot = 7.48 gallons
1.5 gallons / 7.48 gallons = .20
almost there
Dolomite lime - .20 cu ft X 40g = 8 grams of lime. Gypsum is .20X10g = 2 grams gypsum.

I bought 40 pound bags of both from an ag supply store for $6 or $7 each. To say I had some left over after making a couple 20 gallon batches of mix is an understatement. I spread the gypsum in the garden to help break up our heavy clay soil. I use some of the lime on the yard where our dogs pee.

After doing this I switched to coco and perlite. Perlite weighs nothing and compacted bricks of coco are easy to deal with and store.


This was a lot of help, thank you! Did a lot of math and came up with 21 Cups of Peat and Vermiculite would be added to that mix for a 1.5 gallon pot and when I transplant to my final pot (5 gallons) it would be 69.75 Cups

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