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Tell us about your pH range

Are you a 6.2 die-hard? Do your pH ranges fluctuate like the weather? Are you feeling antagonistic towards antagonism? Does your system do the work for you? This thread is to discuss all things pH.

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So water PH directly effects soil PH. We also know that PH needs of the cannabis plant changes during its life cycle. Some forms like folliar feeding like the water above 7.0 .
Keep in mind soil is how i grow always have always will. its more forgiving then other mediums. Soil likes a 7.0 PH. So if you are feeding with water that is consistantly below, Lets says 6.5 your soil PH will drop. thus causing you issues down the line.
I really stay around 6.5 to 6.8. i dont have issues with roots or soil. and my plants stay nice and healthy always and forever

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Growing in Rockwool, coco, DWC, or NFT I keep my nutrient solution between 5.5-5.7
Even more importantly I check the runoff of drain to waste and the reservoir of recirculating systems daily and adjust if necessary. If the rootzone pH is out of range, adjusting feed pH to bring it back into line has always worked best for me. While there is a large pH range(5.0-6.0) that gives great results in hydroponic systems, it’s up to the grower to figure out where in that range they are getting the most from their nutrients for the selected crop or cultivar they are growing.

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My field ranged from about 6.2 to 6.8 this year.

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I would thought I died if I had a pH below 7 from a tap in the Midwest. In Kansas City, we ran a consistent 7.4 and a buffering compacity of 400 to 500 grains. We would uses phosphoric acid in our fertilizer calculations. We would shoot for 6.8 to 7 as the final pH.

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Right? My well water pH is 9.5. :rofl:

My pond pH is 7.4, which works well with our always perpetually acidifying PNW soil.

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Give 9.5 and no buffering and I could work with that.

I dream of acid soils in my sleep. We want to retire to the Bellingham, Washington area.

I want fresh food, legal pot and temperate rainforest. Tired of the great white northern Minnesota. I need more blue.

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My well water is well buffered, it takes a good bit of HCl to bring it down.

If acidic soils and ideal cannabis climate are your desire, the PNW is for you! Our soil is pretty easy to dial in. Much better than saline-alkaline soils… :tired_face:

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We are an indoor grow in Oregon, our well is perfect, usually at 6.5, climbs a bit in summer fall 7.0, hardly any bicarbonate so added fertilizer drops the ph. We add acid for propigation to get ph to 6.0. We use a custom soilless mix that is buffered to 6.5-6.8 with lime. Nothing changes no mater what we put in the soil.

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Do you weigh at each growth stage?

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5.2-5.4 pH regardless of medium for maximum uptake entire grow for tomatoe and canna. I will start at 4.9-5.0 for seedlings until the rest of the organics are in the mix and soil food web is complete it will bump up on it’s own.
In a pefect world 5.3 for soil pH. +/- .1.
Will shout out to Bluelab for the Leap Probe make life super easy.

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yes ph ranges are different for each stage of life. i think a lot of growers miss this, or dont know about it. the difference is pretty noticable.

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I fluctuate my pH across a range from 5.8 to 6.8. My theory behind this practice lies in synergism and antagonism (and I took a page from the book of picky eaters everywhere: certain micro and macro nutrients are available at different pH ranges so I provide a “menu” of “food” for my plants. Just my theory though :wink:

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its something like that. my foliar feed is like 7.2 7.5 ish. but yes micro and macro avalability is at differnet PH ranges.

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If I foliar feed, I always try to be a minimum of 7.2 pH. Higher pH will have antifungal properties and will create an inhospitable environment for PM and molds to form on the leaf surface.

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Why do you foliar feed? Leaves are a poor substitute for roots. You only have the stomata as an access point, the arrangement of the surface dermal layer and the orientation of the charge discourages absorption. I have used some traces as a foliar. But my goal is like 1 ppm or less of the molecule.

I did not foliar feed, it would leave spots. Hard water.

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At 5.3 pH P K absorbtion rates are 10 times higher than at 6.5 soil pH. At the same time N absorbtion is completely maxed out with most of the micros as well at 5.3
It’s a super nice cost saving because the floodgates are wide open so backing off on base nutes is good idea especially in synthetic or hybrid programs.
Let me dig a study done by USC specifically for canna with a graph on absorbtion rates per individual nutrient. My info and expirience is based off their study.
I know, I said the same thing.
Whaaat 5.3?
That’s F’n crazy. Or is it?
Keep me in mind cause I would like a high five when your thrilled with the results.

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Here is that chart. I try to avoid 6.3.
7.0 not bad but micros can’t flow like they should.

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