~ThE pRoMiX tHrEaD~

~The Promix Thread~

I have been using promix for a few years now and along the way I have learned a few things that I would like to share. While I specifically use the term "Promix" I think that this information can apply to other similar mediums like sunshine mix and other peat based mixes.

Although I am making the switch to coco I want to put up some of what I have learned over the years for anyone who is growing in straight promix. There doesn't seem to be any threads that are specifically for promix growers - so I thought I would create a promix thread. Hopefully this can help anyone who plans on growing in promix or is currently having some trouble with it.

I will try to split this up into different sections so it is easier to read and follow.

1.Medium
The type of promix I have used has always been the promix HP with mycroiza.
This mix has perlite, dolomite lime added as well. So throughout this thread when I am referring to promix it will be the promix HP.
First off is mixing up your promix. For seedlings I usually use straight Promix (PM) and might add some Earth Worm Castings (EWC). I veg in oasis cubes and once I got good roots I transplant into solo cups of PM. For the first few week I find that all that's needed is some rapid start (GH) and some superthrive. Other than that just straight water that I ph to around 6. Promix is a spikes mix and the ph should be around 5.8-6.2. However I will get to that a bit later.
So for clones and seedlings I just use the mix straight out of the bag.
*tip - when transplanting clones you can dip the roots into some subculture M(GH) or other powered mycroiza or sprinkle it in the hole where going to put your cutting, make sure it is touching the roots.

Now when running promix I have found that over time the PH tends to drop, this is because as pear moss breaks down it becomes more acidic. Therefore adding more dolomite lime is very helpful. I will add one - two tablespoons.
So what I do is get a tote or bin and dump in all the promix I am going to use. Then I add 30-40% perlite - the chunkier stuff is better but any kind will do. I will mix that into the promix and add in the dolomite lime (or you can add the dolomite lime after you have put your promix in the pot, this is just so you know you have your 1tbls per gal) either way is fine. At this stage you can add some mycroiza or something like subculture B (just using the GH brand as an example anything like that will be fine)

Then once everything is mixed in really well you can fill you pots.
I personally go from solo cups to 1 gallon to 2 or 3 gal pots (depending on how long I veg for) I find a 2 gal pot will work for 30 day veg and 60 day flower cycle but having a bigger pot is fine as well. I believe I have heard the rule of thumb is 1 gal for every month the plant will be in there. So by that logic. 3 gal pot would b good for a 30 day veg and 8-9week flower. But I have used 2 gal pots with 30 day veg with no problems.

2.Watering & Feeding

Promix needs to have a wet/dry cycle. If you overwater you will find your roots will not get the oxygen they need and you will get all sorts of problems. This is why I go from solo to 1 to 2/3 gal pots because the less medium the faster it will dry and I have had problems going from a solo cup to a 2 or 3 gal pot and overwatering - it takes forever to dry out if you roots aren't established.
So when you first transplant you want to give light feeding or just plain water depending on how your plants are looking. (Most important thing is to read your plants if they look hungry Feed them, if they look overfed then just give them straight water).
The thing about promix is that it accumulates the salts in the nutrients over time (this assumes you are not using organics. That's a whole different article that I am too inexperienced to write)
So on the first couple feeding once you have transplanted you will need to give a low strength nutrient solution or ph balanced water (always helps to add some superthrive/roots excel/rapid start to your water)
This is because you don't want to feed it where you get a lot of runoff because it will stay wet too long - I find smaller feeds that have low strength are better and then you can feed more frequently.
As I said you want a nice wet m/dry cycle - however with that being said you do not want to mix to totally dry out-there is that perfect dryness where the pot is light but it is not bone dry. If you let it dry out too much when you go to water it will just run down the sides and also the concentration of nutrients will rise in the medium and cause problems.
Once you have established a good root system you will want to get some runoff when you are feeding with nutrients to wash out some of the build up. It takes some trial and error to figure out how much to feed and how often to feed plain water. I found if I keep my nutrients low like .6-.8 ec in veg and 1.0-1.2 in flower and water every other feed this is a good starting point and you can read your plants if they are hungry skip a plain watering if they are looking overfed do two waterings in a row and maybe get some runoff m. Usually when I feed plain water I don't feed to runoff unless I suspect things are to high.
Now runoff - this can be tricky. One thing I have found when using regular pots (usually have 4 holes around the bottom/sides and one in the middle of the bottom of the pot) I have found the best way to get a reading from the runoff is to lift the pot and collect the runoff from the bottom hole, for some reason I always get different readings when measuring from the side holes as opposed to the bottom.
The runoff doesn't seem to be a really good indication of what's going on in the root zone (I have read slurry tests are better for this purpose)
The runoff tends to be higher than the solution going in, probably because of accumulation but I try not to pay too much attention until I see there is problems starting and then I check the runoff if you constantly are making adjustments or flushing because your runoff is high it seems like you may cause more problems - I find if you keep your ec low and keep the plant happy you don't have to worry about the runoff ec too much (someone correct me if they have another opinion on this) however with that said, if your runoff is super high you might want to think about flushing the build up out before you get problems.
This is also why I add so much perlite to the mix because it is a lot easier to flush and makes for an overall lighter airy mix.
So basically do not over water and make sure you keep the ec/ppm of your solution low to avoid overfeeding and alternative feeding and plain water.

3.PH
One of the most important aspects of growing is the PH of your solution and your medium.
As I stated before promix is made up of mostly peat moss, which tends to become acidic as it breaks down. I have never had any issues of high ph when running promix it's always an issue of being to low if anything.
And because the salts accumulate in the mix this tends to drive the ph down as well. So acidic peat moss and salt build up are a recipe for low ph which locks out you me nutrients.
I find that most of the time when I see growers asking for help and to diagnose a problem it is most likely caused by a ph problem.
So how do you avoid this from happening. Well first off adding a good amount of dolomite lime at the start, as I mentioned above is a good idea. And testing your runoff with a good digital ph meter is key (the drops are really hard to be accrual with - when using drops I was constantly ph'ing my mix too low and didn't realize this until I got a digital meter. Also keeping your nutrient solution at the proper ph and keeping the ec/ppm level low is really helpful. I tend to jn my ph closer to 6 these days and it seems to help things - I used to run it at 5.8 but it seemed like it was always to low when I tested runoff.
If you find your ph is low and having trouble bringing it up adding some more dolomite lime as a to dressing can help but it does take a bit of time to work. You can also raise your ph of your solution or plain water when feeding (don't raise it too much at once or you will get problems from a huge ph swing)
Ph is very Important and if anyone has anything to add on this, please feel free to add to this.
I find I always end up with my ph too low at the end of the grow. So keep that in mind when you see problems creep up.

4.Roots
A healthy root zone is crucial to healthy plants and big yields. I have found that the way to keep nice healthy roots is to ensure that the roots get plenty of oxygen and the key to this is not to overwater and not to underwater and let the roots dry out. I have also found that the added fungi (subcultureM or mycroiza) and beneficial Bacteria also help the roots stay healthy.
I have also gotten into many battles with fungus gnats so it's always good to have some yellow sticky paper around your pots so you can catch those little bastards early.

All in all promix can be a lot more forgiving than many other hydro methods but it does have its own challenges. It is a good medium to use for growing any size of plant. If anyone has anything to add regarding promix or sunshine mix (as they are kind of the same thing) please post your experience. Or if you have any questions about promix please feel free to ask and hopefully myself or someone can help answer your question or help solve a problem.

Buds in Promix

Buds in Promix

Some old bud shots from a couple runs ago.



Sorry about the sideways pics not sure how to fix that, any suggestions? And the picture quality isn't the best.

In running promix bx with no ammendments. I use pure blendpro and a booster.i use it right out of the bag an ph all of my solutions at 6.0. Never have a ph issue yet. i treat my promix plants exactly the same as my rockwool plants. Same solution strength and all justin diffrent size reservoirs. Also when it comes to feeding the pomix, i just check weight. Feed when light till its semi heavy. Usually every other day waterings

Promix is not hydroponics move this post!

Promix is not even an inert growing medium and is not hydroponics!

Hydroponics entails growing in a liquid environment not in a soil. Nowadays most choose to use coco over promix as promix is highly acidic in nature and is not inert also coco holds a better water to air ratio than does plain straight peat moss ie promix. Promix is best watered at 6.5+ ph also. That is not normal with hydroponic applications where 5.7 is found to be optimum. Also peat moss does not perform well without additional amendments.

You arent going to reinvent the wheel posting promix as a hydroponic medium when it has been used as an organic soil amendment for decades. Sorry but peace out.

i wonder if i can get promix here.

LostTribe said:

Hydroponics entails growing in a liquid environment not in a soil. Nowadays most choose to use coco over promix as promix is highly acidic in nature and is not inert also coco holds a better water to air ratio than does plain straight peat moss ie promix. Promix is best watered at 6.5+ ph also. That is not normal with hydroponic applications where 5.7 is found to be optimum. Also peat moss does not perform well without additional amendments.

You arent going to reinvent the wheel posting promix as a hydroponic medium when it has been used as an organic soil amendment for decades. Sorry but peace out.

Click to expand...

Hey thanks for the input - I guess I was just thinking between soil and hydro I look at it more hydro, but you have a very good point and as I said I am switching over to coco myself but just wanted to post some info that I learned over the years. Hopefully it can help...

sorry dude.

look I started out with peat moss like 20 years ago trust me its good stuff but it alone will not produce results. I have tried that so I know very well. Dont just jump off the wagon cuz I said it didnt go in the hydro forum. Personally I dont see why you cant get great results with promix if you do it right. You want like 60 percent promix, 30 percent perlite, 10 percent worm castings. Then you want to add some ammendments like a bit of dolomite lime for the high ph in the peat. Then add some guanos or dont and use a nice fert like earth juice. I used to get great results just switched to straight hydroton and dwc veg for the growth. I used to have to use big pots too 5 gallons minimum or you will have to repot.

Phases; appreciate you taking the time to start a thread, to help others grow successfully in ProMix....there seems to be so much conflicting info on the subject today.

I use straight ProMix, and have a couple questions please.

1)Do you use HP because that's what is available in your area, or do you find it better than the ProMix BX ?...I use BX
2)I use synthetic nutrients & boosters(General Hydroponics) and PH watering solutions to 6-6.2...do you try to "float" your PH, to absorb elements ?
3)Once you add amendments like Wormcasings or Guano, aren't you entering the "hybrid" world of growing ?
4)How often do you check your run-off, and at what PPM would you be concerned to consider a wash-out of media ?

Bwanabud

You right there is a lot of conflicting info regarding promix and other peat based soiless mixes. I hope that this thread could be a place to try and sort things out.

1. I use the HP because it has just perlite, where the BX has vermiculite, which to my understanding holds onto water. I add a lot of perlite as well because I like to have a light, quick drying mix - because I find using it right out of the bag takes a long time to dry out at the beginning stages when roots aren't fully developed and when having to flush the mix out takes forever to dry out (in my room at least).

To be honest I haven't tried out the BX but I imagine they are probably similar, the BX will just retain moisture longer.

2. I use GH nutrients as well, just micro and bloom and maybe a booster. There is a lot of disagreement on the ph issue in peat based mixes, I always find my ph ends up really low, so recently I have started ph'ing my solution a little bit higher like you said 6.0-6.2, to counteract the promix's tendency to pull the ph down. I also use dolomite lime, which I think really helps keep ph more stable.

3. Once you start adding amendments to the mix your basically making it a soil mix, I usually only add some EWC in solo cups so that my clones get some extra nutrients cause I just feed them straight water for first few weeks.

I have also found using EWC tea and alfalfa teas during veg help out a lot, even when using synthetic nutrients, like half organic half Chem style.

4. Now this question is a hard one. There have been a number of times my runoff was up to like 2.4+ ec and I panicked and flushed only to get deficiencies right away and the plants I didn't flush seemed to be fine. The only solid advice I can give is don't just go by your Ppm/ec runoff - you want to read the plant and use the runoff to help diagnose issues. That being said when it comes to promix less is more. I like to run a lower ec and water every other feed, and then if they look hungry feed twice in row of look overfed then water twice in a row.

Hope that helps out. What is your current feeding schedule and amount of nutes you use. I am curious to see how others are running their mix.

LostTribe said:

sorry dude.

look I started out with peat moss like 20 years ago trust me its good stuff but it alone will not produce results. I have tried that so I know very well. Dont just jump off the wagon cuz I said it didnt go in the hydro forum. Personally I dont see why you cant get great results with promix if you do it right. You want like 60 percent promix, 30 percent perlite, 10 percent worm castings. Then you want to add some ammendments like a bit of dolomite lime for the high ph in the peat. Then add some guanos or dont and use a nice fert like earth juice. I used to get great results just switched to straight hydroton and dwc veg for the growth. I used to have to use big pots too 5 gallons minimum or you will have to repot.

Click to expand...

I have definitely got some good result just using promix,lime and lots of perlite, but I agree it is probably best to add amendments and it seems to be a great base for organic soil mixes.

I just find coco to be a lot better for my type of set up, I don't have a ton of room so things get crammed and having to flush or even test runoff with lots of big promix pots is a pain, I run flood and drain with pots of hydrton and dtw coco as well. After comparing everything over the last couple runs I think that coco is best suited for what I need.

Plus hauling bags of promix inside in middle of winter is not my favourite thing to do, and my back is fucked so lifting those bails is not a whole lot of fun, but as you said if done right you can get good results from promix, and I agree amending the mix will be helpful.

Phases said:

Bwanabud
Hope that helps out. What is your current feeding schedule and amount of nutes you use. I am curious to see how others are running their mix.

Click to expand...

Thank you for your thoughts,
I've had some serious issues with my runs, and couldn't find the solution for a long time. After seeking some help, and talking to the manufacturer(GH), I think I'm back on track.

I have 40 ladies @ 3 weeks right now, and switched over to a heavier feed schedule...they seem to be doing well. I always had great veg cycles of 8 weeks, then about 5 weeks into flower they shit the bed on me...fading into yellow top, then brown dried up top leaves. After many fruitless attempts at changing my PH, nutes, Water type(rain water, well water, mixed), organic/hybrid/synthetic style...it looks like my problem is solved, fingers crossed of course

I would do a wash out at 2 weeks into flower, and they would start to revolt. My Run-off was 1200PPM, at 6.2 in...6.1 out. So the real mistake is higher nute shedule & wait till 2000PPM run-off...or the plants tell you they need cleaned.

I'm now feeding EVERY watering as follows(3rd week Indica dominant):
1)5ml per gal. of CalMag
2)8ml per gal. of GH Micro
3)16ml per gal. of GH Bloom
4)2ml per gal. of GH liquid KoolBloom

The KoolBloom feedings will increase 1ml per gal. per week in flower...ending at 5 ml per gal. As I posted in my ProMix thread, I spoke to the GH technical dept. and they were very helpful in info/details. They suggested not using a hybrid grow style, that Floralicious for was taste only, KoolBloom boosts yield and bud size, to float water PH in the 6-6.4 range(I had been running a straight 5.8PH.

I have 55 x HPS 600 lites in flower constantly, perfect room temperatures and humidity, 5 gallon pot size, all plants scrog rack grown unless too tall at flip.

These are some of mine before they head south, I'll get some new& improved pictures today

water only organics with Pro-Mix base:

1 - bale Pro Mix Bx
2 - 1.5 cu ft bag FFOF or equivalent (Vermifire, Roots, etc)
1 - 30# bag EWC
10 gal additional chunky perlite (adjustable to personal preference)

1c alfalfa meal
1c dry molasses
2c kelp meal
2c blood meal
2c bone meal
1c seabird guano
1/4c Sul-Po-Mg
1c azomite
2/3c dolomite
2/3c gypsum
4/3c oyster shell flour

1/2 tbsp BioVam
1/2 tbsp BioAg Vam


Should be around 65 gallons.



dank.Frank

Bwanabud- I be had the same thing happen, all is well then week 5 the problems start to creep up.

So you found heavy feeding and feed every watering at 6-6.4 ph - do you feed until runoff? If so how much runoff, also what size pots are you rocking?

Do you have a link to your promix thread I'd like to check that out.

Frank - thanks for the water only recipe, one day I will do the water only organics, one day!

Phases said:

Bwanabud- I be had the same thing happen, all is well then week 5 the problems start to creep up.

So you found heavy feeding and feed every watering at 6-6.4 ph - do you feed until runoff? If so how much runoff, also what size pots are you rocking?

Do you have a link to your promix thread I'd like to check that out.

Click to expand...

Yes, feeding every round,,,probably in the medium range per GH tech,,,I use 5 gal pots, and 4-6oz run-off maybe.

Here's my PM thread:
https://www.icmag.com/ic/showthread.php?t=317762

If there is one thing for sure, go organic,,,or go pure synthetic, when you try a TRUE hybrid it's tricky. The real problem is this, the fucking work "organic" nutes. Because they can be REAL organics with living biology,,or WANT-A-BE organics with no living biology, but have organic compounds & elements. FoxFarm is the biggest offender of this, they claim organic..but total BS because only Big Bloom is truly organic.

Your synthetic plant grow can get elements from organic product, but without a microbe colony you're wasting your time...thus organic guys always say "feed the soil, not the plant". They are 100% correct, the organic beast, is totally different than the synthetic one...and mixing is really only feeding the grower's ego, not the plant....JMHO

Yeah I tend to stick with straight synthetics - however as I had mentioned in an earlier post when I start vegging in solo cups I may use some EWCs a with superthrive untill they are big enough to start feeding.

For the most part I just use the promix straight up with either PBP gro for veg or just start with GH micro/bloom.

You mentioned you use 5 gal pots - how long do you veg before flipping to flower?
I've been doing about 2-3 week veg and just running in 2gal pots, they don't seemed to root bound but I wonder if I should have upped the pot size. I have a side by side with 2 gal promix and 1 gal coco and the coco it just as big and bushy if not bigger - it's crazy. I want to be able to set up an automated feeding system, I think I am done with the hand feeding.

Phases said:

You mentioned you use 5 gal pots - how long do you veg before flipping to flower?
I've been doing about 2-3 week veg and just running in 2gal pots, they don't seemed to root bound but I wonder if I should have upped the pot size. I have a side by side with 2 gal promix and 1 gal coco and the coco it just as big and bushy if not bigger - it's crazy. I want to be able to set up an automated feeding system, I think I am done with the hand feeding.

Click to expand...

I start my clones in 4" pots, then transplant to 2 gallon pots, then transplant to 5 gallon pots...veg for a total of 8 weeks.

I only allow the plants to get 18"-22" tall, fim/top/super crop the shiit out of them. Trying to get very thick trunk/branches, and 35-40 colas per girl..then I let them loose.

I veg for 8 weeks, because that's the flower cycle of my rooms. While I'm vegging, the flower rooms are finishing, so a constant rotation of filled flowering rooms....run about 200 clones at a time, kill what I don't want/need

I set up and Auto watering system for all of mine, for when I go away/vacation...other than that I hand water because different strains have different needs. I use digital yard sprinkler controllers, with a res mounted pump and tubing,,,then to pvc carburetors/diffusers at each plant. If you can completely control room temps, then the watering schedule is easy...plug the format into the controller, and go drinking for a week

Bwanabud said:

Thank you for your thoughts,
I've had some serious issues with my runs, and couldn't find the solution for a long time. After seeking some help, and talking to the manufacturer(GH), I think I'm back on track.

I have 40 ladies @ 3 weeks right now, and switched over to a heavier feed schedule...they seem to be doing well. I always had great veg cycles of 8 weeks, then about 5 weeks into flower they shit the bed on me...fading into yellow top, then brown dried up top leaves. After many fruitless attempts at changing my PH, nutes, Water type(rain water, well water, mixed), organic/hybrid/synthetic style...it looks like my problem is solved, fingers crossed of course

I would do a wash out at 2 weeks into flower, and they would start to revolt. My Run-off was 1200PPM, at 6.2 in...6.1 out. So the real mistake is higher nute shedule & wait till 2000PPM run-off...or the plants tell you they need cleaned.

I'm now feeding EVERY watering as follows(3rd week Indica dominant):
1)5ml per gal. of CalMag
2)8ml per gal. of GH Micro
3)16ml per gal. of GH Bloom
4)2ml per gal. of GH liquid KoolBloom

The KoolBloom feedings will increase 1ml per gal. per week in flower...ending at 5 ml per gal. As I posted in my ProMix thread, I spoke to the GH technical dept. and they were very helpful in info/details. They suggested not using a hybrid grow style, that Floralicious for was taste only, KoolBloom boosts yield and bud size, to float water PH in the 6-6.4 range(I had been running a straight 5.8PH.

I have 55 x HPS 600 lites in flower constantly, perfect room temperatures and humidity, 5 gallon pot size, all plants scrog rack grown unless too tall at flip.

These are some of mine before they head south, I'll get some new& improved pictures today
[URL=https://www.icmag.com/ic/picture.php?albumid=64823&pictureid=1543892&thumb=1]View Image[/URL] [URL=https://www.icmag.com/ic/picture.php?albumid=64823&pictureid=1543889&thumb=1]View Image[/URL] [URL=https://www.icmag.com/ic/picture.php?albumid=64854&pictureid=1538519&thumb=1]View Image[/URL]

Click to expand...

I was just re reading this post - do you run calmag and the micro at 8ml/gal untill you start your flush?

This run I started to cut back on the micro in week 5, I just hate getting too much N going on in late bloom,

How long did you say you flush for as well?

Trying to see how everyone runs their nutients in promix - everyone senna to have a different way.

I have always done - feed / water / feed / water

but lately I have been doing feed every time with a 1/3 mix.... only problem I have encountered is messing with the nutrient profile because of miscalculating the additive amount vs. base amounts.

handwatering promix seems to be an art form ... different methods for everyone