GOLDBERG71
Well-Known Member
???? if it works for you keep doing it. I'm just posting what I've noticed works for me.
PRO MIX BX WITH MYCORRHIZAE
- Thread starter GOLDBERG71
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GOLDBERG71
Well-Known Member
Soilless mix is peat based and that was what I intended this to be about. It is based on the fact that it is recommended to have a soil PH of 6.5. I always ASSUMED pro mix would be close to that range. When I tested it and it was at 5.7 I was surprised. So I wanted to see who else noticed and if they noticed what they did. It seems there are mixed results. I wanted to run a cycle with soil raised to 6.5 with hardwood ash. That plan might not happen because I had to cull that crop. But in the mean time the crop before that I changed the PH of solution to 6.8 to try and counter the lower PH of the soil and to this point I've had nothing but great results. So my conclusion would be from my results is that raising the PH of my solution has yielded me the results I was wishing for. From now on I'm dropping the ash because it's easier to feed at 6.8 than to make sure 3 cups of ash gets evenly mixed into a 8 CF box of mix. However it would be my guess that raising the soil PH to 6.5 with hardwood ash and feeding at 6.5 PH would do the same thing.
GOLDBERG71
Well-Known Member
I'm using DYNA GRO products also. I've recently dropped grow for foliage pro. I only use bloom from week 4/5 on and even at that point it's on 1 to 3 ratio with foliage pro.
GOLDBERG71
Well-Known Member
You need to do what works for you. Read for information but you can't follow everyone. At some point you need to make your own choices because everyone's growing situation is different. But if you are using Dyna Gro and have problems plenty of people use them on here and I'd follow them over someone who is using different nutes. You also need to realize no 2 pro mixes are the same. I started this thread about pro mix BX. I'd make sure you know which brand the person is using before you listen to them. I've only added pulverized lime and hardwood ash. The lime I'd never use again because it DOESN'T adjust ph. Although I liked the hardwood ash I didn't like mixing it in. Hydrated lime would actually raise the PH. But ever place I've read other than threads whether it's books or nutrient uptake charts ALL say 6.5 is where you want to be. Would you trust a recommendation from a company who sell pro mix that your soil should be at 5.8-6.2? Or would you believe scientific data? I don't know about you but I'm going with the data. That's what lead me to create this thread. I can only speak for myself. I created this thread because I was having a problem with my fan leaves slowly yellowing and drying up after the 4th week of flower and it wasn't from lockout. In my quest to figure out the problem I bought my soil PH tester. When I tested my promix with nothing added and figured out it was 5.7-5.8 I thought I found my problem. Hardwood ash was how I thought I was going to correct it. So I mixed up a new batch of soil and got it to 6.5 with hardwood ash. I never got to flower that batch I've posted about that early today. But when I made that choice I had a batch with ready to flower. Since it was to late to mix anything in the soil I decided to feed at 6.8 to counter the soil PH. Now without testing my soil because I haven't had the need since they look perfect (other than a little damage from spider mites) I can only guess that this combination is resulting in a PH near 6.3??? which still is 0.2 below where I wanted it. But one of the parameters I use is feeding between 6.3-6.8 only because it coincides with the nutrient uptake charts. However despite being lower than I wanted I've noticed that my plants at week 6 in flower have never looked better. So with that info I believe PH was my problem and it starts each time I open a new bale. So for me in a nut shell I'm choosing so solve my problem by feeding at a higher PH rather than mixing in additives like hydrated lime or hardwood ash because it's easier for me. Making sure those additives get even mixed in takes work. My work area is tight on all directions so mixing in additives isn't easy. But putting a few drops of concentrated PH up is much easier for me and therefore the route I will be taking in the future. I hope this helps you.
GOLDBERG71
Well-Known Member
ok I think I'm caught up on what I needed to comment on if not post again please and I'll get back to you.
JDGreen
Well-Known Member
Yes YES Yes, the soil will buffer the ph so just stay under 9 and above 3 and ur good. And i only check.ppms for.my hydro stuff.
Pro-mix BX is pH adjusted during the manufacturing process. If I use it straight out of the bag, I usually pH adjust the input water/nutrient mix but that is probably not even necessary unless you have some weird water source. Normally, however, I cut it with sufficient organics that it doesn't need any further nutrient added, water only. Like most city water, tap is around 7 or so. There is no need to pH adjust for the organic amended mix as it is now soil and it has buffers. True soil-less mediums - like rockwool - don't have buffers, that's why pH is more critical with them.
If anybody can cite a horticultural *professional* recommending obsessive pH monitoring/adjustment for container gardening (NOT mary jane) with Pro-mix BX or equivalent , I would like to see it.
If anybody can cite a horticultural *professional* recommending obsessive pH monitoring/adjustment for container gardening (NOT mary jane) with Pro-mix BX or equivalent , I would like to see it.
Outdoorindica
Well-Known Member
I always used Promix BX, but never added anything just watered in nutrients. It always worked fantastic for me. My Grapefruit Krush that I ran in it for years preferred the watering at a ph of 6.1. Not pH adjusting the water was very harmful to the plants. Promix on its own won't adjust the pH fast enough to not negatively effect the plants in my experience. But I mostly used Fox Farm nutes for my indoor growing. I went with the less is more method because most plants don't need 1000+ ppms if the nutrient uptake is good enough. I'd imagine different nutes react, well differently.. I should mention though, my tap water out of my well is low, something around 5.2.
GOLDBERG71
Well-Known Member
Just stay between 9 and 3 and you are good? Send me some pics of plants you've feed at either 3 or 9 for the entire grow please. That's a must see!
GOLDBERG71
Well-Known Member
This thread is about soilless mix only and specifically pro mix BX. It was only to be about the mix and it's PH and what you did or didn't do to adjust it. Cutting it with organics brings it to places this wasn't meant to go. The bales come mixed and read 5.7 to 5.8. That's the point of the topic. ALL nutrient uptake charts and scientific proof states that cannabis has a sweet spot of a PH of 6.5. Pro mixes are meant to be treated like soil but a clean building block. To which a grower knows there is nothing in there other than sterile mix and we as the grower get to introduce any and all elements at the time we see fit. Without having to consider what was in the mix. That's why we choose pro mix and not organics. We don't want anyone putting anything in our soil.
GOLDBERG71
Well-Known Member
I use dyna gro nutes and NEVER feed over 300 ppm in veg through the first 2 weeks of flower. The next 2 weeks I raise it to 400 ppm and from week 5 on 500 ppm. I don't introduce bloom until after the 4th week and at that point it's only the last 100 ppm of the solution. I just make sure I have plenty of run off and once a month I feed at half strength during flower. It acts as my flush. I use RO water (0 ppm) only I don't want chlorine or anything else in there from the town.
Pro-mix works fine right out of the bag, but it is commonly amended and the manufacturers have nothing to say against it. In any case, you are basically claiming that the Pro-mix manufacturer is shipping a product that needs pH adjustment since they, the professionals, didn't get it right. Furthermore, you seem to feel there is some benefit in testing "runoff". Unless your water pH is screwy, I don't see any need for it. If it were so, this practice would be common among horticultural professionals growing, say, tomatoes. Well, it isn't. That is why I asked for a citation. I've used Pro-mix BX pure, blended, and in raised beds outdoors. Never worried much about the pH. Why would I?
GOLDBERG71
Well-Known Member
There's a million more. But as a general statement 6.5 is what we should be striving for. Of course there may be strains that prefer something slightly different. But in general when you open a bale and the PH is 5.7/5.8 you aren't in optimal range. Some people treat pro mix like HYDRO and for their purposes this very well may be ideal but personally I treat it like soil. If I wanted to treat it like hydro I'd be enriching with CO2 as well. So it's become clear to me I have to do something to bring the PH closer to 6.5. There are many ways to do it. Some might be doing it and not knowing it? I'll say it again I can only comment on either facts or what I've observed. When I started I was feeding at 6.8 and I wasn't having any problems. But in my reading I found information like the above graph. So I started feeding at 6.5 hoping for better results. Instead I've had my fan leaves turn yellow between week 4-6. For some time I thought that was normal figuring it as end of life cycle. I've since figured out that's not the case. So I started looking for my problem and this is where it has brought me. If the soil is 5.8 PH and I feed at 6.5 PH the soil should roughly be 6.15 PH. At that level I was getting great buds but my plants didn't look like I think they should. That's a nice green plant from start to finish. Now that I've adjusted for the soil PH of 5.8 with all solutions with a PH of 6.8. That should leave me a soil with a rough PH of 6.3. Which still is 0.2 PH points below what I consider optimal. However, I'm VERY pleased with the results I'm seeing. The next cycle I might even try a few plants with 7.0 ph and compare those results because that would bring a soil of 6.4 PH. Then depending on what that shows me I would consider pushing it to 7.2 the following run on a couple to reach the optimum of 6.5 PH soil.
GOLDBERG71
Well-Known Member
I've never claimed anything about testing water runoff. I did state I tested it just to see what it was reading ONCE but I'd never trust it! Sorry if I wasn't clearer about that because I didn't mean to give the impression I'm doing any of this due to a PH reading of run off! Nothing could be further from the truth. But these professionals as you call them who I'm not trying to insult are selling a product that some people treat like soil and some people treat like hydro. They aren't creating 2 different products to be treated 2 different ways. That's why most people amend their soil the way they see fit for their style.
PH isn't screwy I'm using bluelab equipment and RO water.
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GOLDBERG71
Well-Known Member
Is there something chewing on the plant in the second picture? or is that from handling? Otherwise they look good. I'm assuming they are under HPS and that's why they don't appear as green as they could? That's my biggest problem with HPS you can't get good shots of the flowers.
GOLDBERG71
Well-Known Member
I'm not doing the work for you. If that chart isn't enough I'm sure with VERY little research on your own you could find plenty of places that will prove my point. It's pretty common knowledge that 6.5 is ideal for soil and 5.8 is ideal for hydro.
GOLDBERG71
Well-Known Member
On second thought since i have a few minutes while the broiler heats up for my steak. MARIJUANA GROWERS INSIDERS GUIDE page 195 second paragraph. "rainwater is excellent for growing plants blah blah blah ......SLIGHTLY ACID TO NEAR NEUTRAL IN PH WHICH IS PERFECT FOR GROWING MJ. Like I said a little research and you'll find 6.5 is optimal for SOIL. I didn't want it to appear I was being snotting and couldn't prove my point. If it's not a fact or I've not seen it in my results I won't comment on it.
