I PH my water to 6.3 - 6.5 every time I water or feed my plants. When I test the ph of the runoff it is always between 7-7.5. I’m not sure why. Is this going to cause a problem or is the runoff supposed to be different? I’m using Mother Earth Groundswell soil.
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PH you water to 5.3 and test your runoff.
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And if the runoff looks good do I return to my normal 6.3 ph watering after that? Then if it rises again repeat this? Am I thinking correctly here?
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Do you have lime in your soil? I would do it like this a few times then go back to your plain water and test again.
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I’m not sure if this soil has lime in it. I didn’t put any in it.
I wouldnt go as low as 5.3… thats extremely out of range and it could swing the other direction.
Maybe 6-6.3. But honestly if they arent mad, I wouldnt be.
Check the back of your bag for ingredients. Pretty sure D Lime is in there because organic style soil usually has lower pH then what we want.
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I wouldn’t either. The pH scale is logarithmic, meaning that the difference between 5.0 and 6.0 is not 1 point. The progression between 5.0 and 6.0 is 10x, meaning for instance, that 5.0 is 10 times as acidic as 6.0.
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Ok, that sounds good. Should I think about flushing with ph water to get it in check or just adjust like you guys say and let it ride?
Pictures would tell the story. I wouldnt flush unless something was drastic. And being around 7 isnt quite time for the nuclear option (flushing)
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Cool. I’m at work right now. I’ll post a pic tonight. Thanks for the info!
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If he’s testing 7 3 out the bottom 6.2 going in, then dropping it a point is the solution. How do you suggest dropping it ? He’s on here posting, so I assume this isn’t just an occasional thing. I suspect tit’s buffers in the soil holding it at 7.
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5.3 is so far out of the range, it could be more detrimental then helpful.
I stated how I would attack the issue. He’s going in at 6.3-6.5. I suggested trying 6.0. Honestly I wouldnt attack it at all assuming plants are not showing signs of trauma. 7 isnt nowhere near as bad as 5.8 let alone 5.3…
I wasnt saying you were completely wrong. Adjust to lower it… incrementally. And yes, that buffer possibly being D Lime. If its the case, flushing with low pH water would not only strip his soil of amendments, but could drastically drop the pH.
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@PurpNGold74 If it is lime, is anything really gonna move it much? I had this same issue last round with 2 plants that had lime. Up to the day of harvest I lowered the ph but it stayed a pH of 7.1. Without the lime it would adjust to his waters pH. What’s the real solution here, not adding lime at all? Outdoors a pH of 7 is fine but I was having issues with those two.
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It may, it may not. Just kinda in general, making adjustments you never want to overcompensate. Make them within the realm of control, so if and when things go off the rails, they are manageable.
Indoors I dont see a pH of 7 causing too much issue until mid/late flower if then. Could have just been that strain giving you problems with high pH. In that case, indoor or outdoor wouldnt have made the difference. Some strains are just resilient and dont care, and others are finicky and throw a fit just because…
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Here are a couple pics of the plant. Fed her bites last night and she seems to look ok. I just noticed a bit of yellow on the leaves in the close up so it got me looking at the ph. I’m also including a picture of the soils ingredients. Thanks all for your responses. I’m going to water at 6 the next time I water and will just keep an eye on it.
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I use Mother Earth Coco Peat. Occasionally my runoff pH is higher than average, just like the numbers you’re seeing, but it’s never caused any problems for my plants. The pH of the runoff is not necessarily representative of the soil pH, so you might be trying to correct an issue that doesn’t exist. A couple of years ago I invested in a good soil pH pen, and that pretty much put this issue to bed for me. Runoff was scaring me because at one point it was as high as 7.8, but the Blue Lab soil pen was saying 6.3.
Are your plants showing signs of something being wrong? If not, I wouldn’t take any action based on high runoff pH, especially a drastic change to your input pH.
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My 1st thought is what are you using to check the PH with. (Meter) Also when is the last time you verified your meter with a fresh clean bottle of 7 ph solution. 
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Great info. I’ll look into a soil pen. I’m not going to do anything drastic because I don’t feel my plant has a drastic problem. As far as I can tell she looks ok besides a bit of yellow on one leaf. I appreciate your input. My ph meter is cheap but seems accurate based on solution testing. I also am contacting mothers earth to see if their is a ph buffer in groundswell just so I know. I may be just ocd on top of being new to growing.
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The soil pH pen was very useful in determining that I didn’t have a problem, but beyond that, I don’t think it was a worthwhile investment overall. I never use it at all anymore because I don’t have any problems for the most part. I do believe there is something in the Mother Earth soils/mediums that makes the runoff pH come out a litte higher sometimes, but it doesn’t seem to have any ill effects. The owner of my local grow store has told me other customers have experienced the exact same thing.
One time my store here was out of the Coco Peat and I can’t remember if I used Groundswell or Terracraft, but I know I went back to the Coco Peat again as soon as it was back in stock. I’ve also used FF and Roots Organic, but my plants are happiest in the Coco Peat!
Let us know what Mother Earth says, you have me curious now!
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The slight yellowing looks like the beginning of Magnesium deficiency. If you have calmag or epsom, it maybe time to give her a mini dose.
You will need a pH pen to get that solution in proper pH range
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