PRO MIX BX WITH MYCORRHIZAE

GOLDBERG71

Well-Known Member
PRO MIX BX WITH MYCORRHIZAE this is my basic soil mix. To date this is the only mix I've used. I buy the 3.8 cubic foot bales and I mix it with a 4 cubic foot bag a extra coarse perlite for better drainage. At first this is all I did was mix, wet and use. After a year or so I decided from my reading on this site I would add a cup of dolomite lime per cubic foot of soil. So for the following year I added 4 cups of dolomite lime to each bale/bag. For the longest time I was fighting my fan leaves from turning yellow. At first I thought my problems were with my soil. Then I thought I wasn't giving them enough N so I gave them a little more. Finally I thought it was my not understanding the plants were dry. I start in 1 gallon pots and then transplant into 5 gallon squat pots. Since I was still having the occasional plant have it's fan leaves slowly go yellow. I began to think about the soil again. This time I started to think that although I'm lifting each pot daily and judging the need of water by weight. I might be fooling myself because the center root mass 1 gallon could be dry but the other 4 gallons of soil could still be 90% saturated making harder for the plant to suck up the nutes?

Well this grow it turns out I had my first bout with bugs other than fungus gnats. So the issue I noticed with the leaves was actually from spider mites. I've solved that problem. But I focused on my soil at first. The first thing I did was flush the plants with plain RO water. I've read that you shouldn't trust tests of runoff water but I decided to test it just so I could take notes. What I found was an average PH of 6 and 400 PPM. The ph was as low as 5.9 and as high as 6.2. The PPM was a low of 350 and a max of 450. This run I'm trying the less is more theory so I've never fed above 300 PPM at the time of the test and all watering/feeding was at 6.5 PH. Not wanting to put to much faith in the runoff numbers last night I decided to PH test my UNUSED soil. This is probably where I should have started because what I found out was my UNUSED soil tested at 5.7 PH.

A few months ago I was told by a guy I trust to eliminate the lime. I didn't ask question I just stopped using it. I won't be able to compare the results because of the spider mites this time. But after the low PH test on unused soil I started googling PH and raising the soil PH. I found 5 things you can add to your soil to raise the PH. They are dolomite lime, hardwood ash, bone meal, crushed marble, crushed oyster shells.

DOLOMITE LIME - 15-45% MAGNESIUM CARBONATE 85-55% CALCIUM CARBONATE

HARDWOOD ASH - 10% POTASH 1% PHOSPHATE + TRACE AMOUNTS OF IRON, MANGANESE, BORON, COPPER, AND ZINC

BONE MEAL - CALCIUM AND PHOSPHORUS (COULDN'T FIND %)

CRUSHED MARBLE - ? COULDN'T FIND WHAT IF ANYTHING IT SUPPLIED TO THE SOIL.

CRUSHED OYSTER SHELLS - 96% CALCIUM CARBONATE AND 10 MICRONUTRIENTS.

I haven't been able to contact my trusted source yet but I'd imagine he will tell me that dolomite lime provides to much magnesium and calcium and those numbers would support that. At this point I'm no longer going to guess. Tomorrow I'm going to clean my mixing box and mix up a new batch of soil and box up a sample and send it off to be tested by the local college. They charge 2 bucks for a PH test and 28 bucks for a PH and nutrient test and they'll recommend the amendments to the soil. I figure since I only mix the pro mix with perlite this info will provide me the perfect soil until they change their recipe at promix. I just thought this info could help others. Right now it seems to me that hardwood ash would be the way to go. Since the whole idea behind soilless mix is to be adding what we want when we want to the soil via feeding it and the ash adds the least.

Does anyone have any helpful input? I'm really curious if anyone is using hardwood ash?
 

chuck estevez

Well-Known Member
seems they already add limestone for you

  • SPHAGNUM PEAT MOSS (75-85%) ?
  • PERLITE ?
  • VERMICULITE ?
  • LIMESTONE ?
    Used to adjust pH to optimum range. Also a source of Calcium and Magnesium.

  • WETTING AGENT ?
  • MYCORRHIZAE™ PREMIER TECH (Glomus intraradices) ?
 

GOLDBERG71

Well-Known Member
seems they already add limestone for you

  • SPHAGNUM PEAT MOSS (75-85%) ?
  • PERLITE ?
  • VERMICULITE ?
  • LIMESTONE ?
    Used to adjust pH to optimum range. Also a source of Calcium and Magnesium.

  • WETTING AGENT ?
  • MYCORRHIZAE™ PREMIER TECH (Glomus intraradices) ?
Yes But I PH tested the soil and it was at 5.7. Optimum PH is 6.5. You are correct there is some lime in the mix already. That sort of also works to my point. If they have already mixed in dolomite lime why add more calcium and magnesium? It's also in the nutes when we feed. And I can't remove them from the bottle. That's why I'm looking at hardwood ash. It adds less of those and provides micronutrients Not in dolomite lime. Those micronutrients are in much less concentrations than calcium or magnesium in the nute we feed from the bottles.
 

chuck estevez

Well-Known Member
have you ever just let the mix do what it suppose to do and buffer the ph for you? Measuring run off is just that, run off, not the ph of the soil. Temperature can change ph you know.
 

GOLDBERG71

Well-Known Member
have you ever just let the mix do what it suppose to do and buffer the ph for you? Measuring run off is just that, run off, not the ph of the soil. Temperature can change ph you know.
Yes I started with straight bales and perlite alone after a year or so I tried adding a lime. I had runs both ways where some leaves started to yellow after about the 4th week of flowerer. Some runs it was worse than others. Some runs I had no issues. But I figure that's all part of the learning curve. The measurements I took I realize are from runoff and many say don't trust it. I'm not I did it because I had the time while I was flushing. The saucers kept filling so I had to empty them. During that time I just wanted to take notes. This way I have notes to check with the next run hopefully under better conditions. However the PH test I did on my UNUSED mix was a test of the actual soil not the runoff. I have a bluelab soil ph meter and another combo meter for the nutrients. Everything I've read so far says the soil should have a PH of 6.5. Until a few days ago I was under the belief that soilless mix was PH neutral. In my mind that is a PH of 7. I feed at a PH of 6.5. Whenever I have tested my soil PH it has been right there 6.3-6.7 but I've only tested right after feeding at 6.5. I guess I should test it before I feed the next time just to see what it reads then. But not to get off the point. The only reason I'm thinking about this is based on the test I did to my UNUSED soil not any previous runs or this bout I had with spider mites.
I just happened to test my soil mix before using it to gather data. That data suprised me. Since I was getting data from the middle of flower I wanted to test the unused soil so I can compare them both with the data I get at the end of the cycle. The next grow I plan on testing every week or 2 just so I can have notes to look back on and compare if need be in the future. Maybe I'm wrong but peat moss carries with it low PH and that is a major part of the mix. So if I just learned that my soil starts at a PH of 5.7 before I use it. Wouldn't it be smart to get it closer to 6.5 PH while I'm mixing it? In addition to that from what I've read once the soil is in the pot with a plant it's not easy to change the soil PH and if you do it has to be done very slowly. So my thinking is since we all now it's easier to start out right and maintain it than it is to start of wrong and correct it during the grow. Wouldn't it be easier to maintain a soil PH of 6.5 if I started at 6.5?
 
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GOLDBERG71

Well-Known Member
Well I decided sending soil out to be tested was a waste of time and money. Since I'm only adding perlite there's nothing they could tell me different than the label and a ph test can tell me. I broke open a new bale and mixed it well over 2 days. The test came out just the same as it did on the mix that had sat it my mixing box for a couple of weeks - 5.7. Then I pulled out the new ph probe because I didn't fully trust the old one and after calibrating it I got the same reading.

So Ive decided that for this batch of soil I'm going to use hardwood ash to raise the PH to 6.5. After speaking with a guy I trust he beleives I'm over thinking this. But I've decided it's time for me to start following my gut. So I took the easy way out and used a rough figure given in an article to calculate how much to use. Im not sure if I calculated wrong or if it was the difference between liquid and dry measure that went wrong. One was surely off but I got lucky because I started by using half the amount (3 cups) and got a perfect reading of 6.5. So it will take some time for me to be able to post my results but I will do so after the harvest. My first results will be a batch that was started in 1 gallon pots with the old mix (5.7) then transplanted in to a 5 gallon pot with the new soil (6.5). Assuming I don't see negative results I'm going to have the following batch done completely with PH corrected soil.
 

az2000

Well-Known Member
That's why I'm looking at hardwood ash. It adds less of those and provides micronutrients Not in dolomite lime. Those micronutrients are in much less concentrations than calcium or magnesium in the nute we feed from the bottles.
If I wanted to raise the ph of my Pro-Mix without using dolomite (which, as you note, can add more ca/mg than necessary) I'd use hydrated lime. 3/4 tsp/gal raises it 1 full point. I'd use about 3/8 tsp/gal to get it to 6.5 from 5.8.

My Pro-Mix HP measures 5.8 out of the bag too. I add Kellogg Patio Plus potting mix which is about 7.0. The amount I use results in 6.2. That's been close enough for me. But, I've thought about adding 1/8-1/4 tsp hydrated lime to bump it to 6.5.
 

GOLDBERG71

Well-Known Member
If I wanted to raise the ph of my Pro-Mix without using dolomite (which, as you note, can add more ca/mg than necessary) I'd use hydrated lime. 3/4 tsp/gal raises it 1 full point. I'd use about 3/8 tsp/gal to get it to 6.5 from 5.8.

My Pro-Mix HP measures 5.8 out of the bag too. I add Kellogg Patio Plus potting mix which is about 7.0. The amount I use results in 6.2. That's been close enough for me. But, I've thought about adding 1/8-1/4 tsp hydrated lime to bump it to 6.5.
I saw that mentioned but only in one place and they said be very cautious. So I didn't really investigate it. But that sounds like something I might want to try next since I've already started with HWA.
 

az2000

Well-Known Member
Call me crazy but pro mix is a soil less mix, correct? Ive read a lower ph is needed for a soil less mix so it sounds perfect to me
Yes, that's true. Nothing wrong with Pro-Mix. If you were replying to me, the reason I wanted to raise the ph is that I'd like to have a soil, not soilless. I want the microbial activity, the use of some organic fertilizer products, etc. Most bagged soil's are too dark and rich for my tastes. I like the light texture of Pro-Mix, but just slightly soiled. I'm having pretty good results with the mix I mentioned above, and a synthetic/organic nutrient blend.

I had good results with Pro-Mix by itself and GH Flora 3-part (purely synthetic). But, I notice a smoother richer taste using more organic sources. I think some soil is better for that.
 

jpizzle4shizzle

Well-Known Member
Yes, that's true. Nothing wrong with Pro-Mix. If you were replying to me, the reason I wanted to raise the ph is that I'd like to have a soil, not soilless. I want the microbial activity, the use of some organic fertilizer products, etc. Most bagged soil's are too dark and rich for my tastes. I like the light texture of Pro-Mix, but just slightly soiled. I'm having pretty good results with the mix I mentioned above, and a synthetic/organic nutrient blend.

I had good results with Pro-Mix by itself and GH Flora 3-part (purely synthetic). But, I notice a smoother richer taste using more organic sources. I think some soil is better for that.
My bad, i guess I need to learn how to read lol ive used some very clay dirt from the backyard and the mj loved it because I wasn't a fan of the soils available for sale here. So I feel your pain brother hopefully your mix has continued success
 

2Hearts

Well-Known Member
Im in Plagron Promix it is peat eartworm cast and lime and wouldnt add any additional as its good to go out the bag.

Earthworm cast work well with acidic peat and give you an organic start on top of all the goodies living in the peat as a well know ph fact although how they negate the ph issue is not well understood just that they do.

Is my idea.
 

Jalan42510

Member
Promix bx at 5.9 with no lime has always worked great for me. In the beginning I treated bx as an exclusive soil. The breakdown state of organic matter in promix is closer to hydro than soil in my opinion. I had great difficulty at 6.3 with nute uptake.
 

GOLDBERG71

Well-Known Member
Everything I've read says that the sweet spot for soil is 6.5 and for hydroponics is 5.8 PH. I've seen where some say soilless mixes are similar to hydroponics. But honestly I don't see it that way. I prefer to look at it this way.

With true hydroponics, the nutrient solution is constantly flowing by the roots and must be continuously monitored and adjusted to provide the ideal pH and proper levels of each required nutrient. With a soilless medium, the plants receive nutrients from the soil solution and nutrients retained by the growing medium after being watered with a fertilizer solution. Plants will then take up these nutrients as they are needed.

That seems a lot more like STERILE SOIL to me. The biggest difference I see between soil and soilless is that without testing soil you don't know what's in it. Where as a soilless mix is not only sterile but a blank slate. That gives the grower piece of mind because we know there's nothing in there we didn't add to it. Bearing that in mind naturally that means I think 6.5 is optimum.
 

lonzo212

Well-Known Member
Yes, that's true. Nothing wrong with Pro-Mix. If you were replying to me, the reason I wanted to raise the ph is that I'd like to have a soil, not soilless. I want the microbial activity, the use of some organic fertilizer products, etc. Most bagged soil's are too dark and rich for my tastes. I like the light texture of Pro-Mix, but just slightly soiled. I'm having pretty good results with the mix I mentioned above, and a synthetic/organic nutrient blend.

I had good results with Pro-Mix by itself and GH Flora 3-part (purely synthetic). But, I notice a smoother richer taste using more organic sources. I think some soil is better for that.
sir, pro mix with perlite alone is ok to grow in? my girls are in that mix...I didn't want run any issues or touch em again, jus grow....should be ok?
 

az2000

Well-Known Member
sir, pro mix with perlite alone is ok to grow in? my girls are in that mix...I didn't want run any issues or touch em again, jus grow....should be ok?
I like to add perlite. I just think faster drainage and drying is always better, at least for this style of growing. When I used Pro-Mix HP by itself, I added 10-20% perlite. (I did ph 5.8 in veg, 6.2 in flower. I feel like I confused this topic when I talked about my addition of soil in a previous post, and how I shoot for 6.4-6.5.).

When I mix Pro-Mix HP with 20% Kellogg Patio Plus potting mix (soil), I add 20% perlite. I think it could be higher. (I do ph 6.4-6.5.).

I think a big benefit is aerating the soil. I have a ph soil probe with a thick 3/8" diameter rod. I swear I think my plants do better after I probe the soil. I keep intending to buy a 1/4" alumunum rod, file it down to a round point, bend a handle at the top.
 

lonzo212

Well-Known Member
I like to add perlite. I just think faster drainage and drying is always better, at least for this style of growing. When I used Pro-Mix HP by itself, I added 10-20% perlite. (I did ph 5.8 in veg, 6.2 in flower. I feel like I confused this topic when I talked about my addition of soil in a previous post, and how I shoot for 6.4-6.5.).

When I mix Pro-Mix HP with 20% Kellogg Patio Plus potting mix (soil), I add 20% perlite. I think it could be higher. (I do ph 6.4-6.5.).

I think a big benefit is aerating the soil. I have a ph soil probe with a thick 3/8" diameter rod. I swear I think my plants do better after I probe the soil. I keep intending to buy a 1/4" alumunum rod, file it down to a round point, bend a handle at the top.
my water is 6.8...using pro tekt...which raises ph..should be good?
 

az2000

Well-Known Member
my water is 6.8...using pro tekt...which raises ph..should be good?
For straight Pro-Mix your final nutrient solution ph should be 5.8 in veg, 6.2 in flower (lower is fine, but it seemed like 6.1-6.2 was good in flower). You can use Pro-Tekt as a ph up to some extent.
 

turbobuzz

Well-Known Member
image.jpg Damn, TMI! I use the bx and don't do a damn thing to it. I just use my nutes. I have great results. The plants below are grown just like I say. Lime is already mixed in.
 
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