Promix HP versus potting “soil”

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Kitinkbootl

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I am on my forth batch of plants, and am using Promix, but it has no nutrients, like potting mix, so I am wondering about how to regulate the Ph. I bought a Ph reader, and the first day I used it with fertilizer, after regulating the Ph, then adding the nutrients, the Ph was below 4! It took a third of my bottle of my Ph Up to bring it to 6.0...
Help...
First, what is optimal Ph for plants in flower and is it different than in veg. I have been running at 6.0, pr so I thought...
Second, how do I monitor and regulate the Ph in the soil? Is Promix typically really low? I am using the growing medium Promix HP.
What is better promix with lots of additives, and if so what and how often, or potting “soil” with nutrients already there...
I am currently into fourth week of flower, everything looks awesome, but I am feeding every other watering, and trying to regulate the Ph. I use a bloom feetilizer, a grow big, and mix “Iguana food” and a fish emulsion. I will need to get the NPK of each, but it seems high in the P and K.
Thanks!
 
Jimster

Jimster

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I have grown in Promix HP for 30+ years and never had any problems at all with it. Could your Ph meter be off? I have never had to adjust my ph in all those years, although I add a handful of wood ashes to provide minerals. Promix is usually pretty good at buffering Ph... you don't normally see big swings in Ph. I use Jacks 20-20-20 fertilizer and not much else. Something is wrong, but I don't think the Promix has a Ph of 4. I feed every 10 days. Some nutrients/fertilizers can lower the Ph, but 4 is pretty low.
Be really careful with the Ph, if it gets too far out of whack, you will start seeing deficiencies and other issues. Most folks keep their Ph around 6.5. How are you checking the Ph? Are you doing a slurry test, or using a meter in the soil? The meters can be very finicky, with a slurry test being the most accurate... all you do is put dirt into a test tube, add a few drops of magic juice, and the resulting color will tell you the Ph accurately. Promix is buffered, which should prevent the Ph from dropping so much. This is interesting, please keep me n the loop!
 
oldskol4evr

oldskol4evr

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go to old reliable ,drops for the ph test,pro mix is peat moss,so is potting soil,they both have there own amends to make things work,peat moss is acidic,i use it in my soil to keep my ph at 6.5 both indoor meds and outdoor veggies,my potato soil i keep at 5.5 and that how i drop my ph with peat,like jimster said check the ph acurite with a slurry test
 
OldManRiver

OldManRiver

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If you need to bring the soil pH up, Lilly soil sweet will work far better than pH'ing your water.
 
Beachwalker

Beachwalker

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I am on my forth batch of plants, and am using Promix, but it has no nutrients, like potting mix, so I am wondering about how to regulate the Ph. I bought a Ph reader, and the first day I used it with fertilizer, after regulating the Ph, then adding the nutrients, the Ph was below 4! It took a third of my bottle of my Ph Up to bring it to 6.0...
Help...
First, what is optimal Ph for plants in flower and is it different than in veg. I have been running at 6.0, pr so I thought...
Second, how do I monitor and regulate the Ph in the soil? Is Promix typically really low? I am using the growing medium Promix HP.
What is better promix with lots of additives, and if so what and how often, or potting “soil” with nutrients already there...
I am currently into fourth week of flower, everything looks awesome, but I am feeding every other watering, and trying to regulate the Ph. I use a bloom feetilizer, a grow big, and mix “Iguana food” and a fish emulsion. I will need to get the NPK of each, but it seems high in the P and K.
Thanks!
I agree with Jim, the pH reading of under 4 seems like there might be something wrong in the reading and/or equipment ? Recheck your steps and if necessary post and ask questions if there's something you're not understanding regarding calibration of pH equipment, or as already suggested pH drops will read true

I have no input on promix but seems like a lot of good information is above, however in soil I add about a tablespoon of lime per gallon of soil to maintain a proper soil pH, good luck!
 
Jimster

Jimster

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However in soil I add about a tablespoon of lime per gallon of soil to maintain a proper soil pH, good luck!
I use wood ashes in place of lime, since it has more nutrients and micronutrients, but lime is great for raising or "Sweetening" the soil. Either one works well, with wood ashes needing more to accomplish the same thing as lime. There was another member who said that they had Ph problems with Promix, with inconstant PH levels between different batches of Promix and a fairly wide swing... between 5.0 and 7.8 or something like that... but not 4. It could also depend on where the PH is measured...soil testing, water outflow from growing medium... they can all show variation depending on where and how the Ph is checked. I love mysteries! My concern is that the big dose of Ph up could cause issues with nute lock in the event that the Ph wasn't out of bounds before treated with Ph up. Keep your eyes out for nutrient deficiencies in this particular plant, since it might take a while to show up... IF there are any! Keep up the good work!!
 
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