Soil PH Question-FoxFarm Soil

I am using light warrior with added perlite in week 4 now--my question is that I am getting ready to transplant from 20 ounce cups to 1 gallon containers. Foxfarm says its light warrior and ocean are ph bal between 6 and 7. My RO water is bal to 6.2(I use a Hanna and 7.0 sol. to make sure it's accurate). Last night I flushed the cups with 100 ounces of pure water(the water was running clear out of the cups), I collected the last 20 ounces and checked the ph---to my surprise the ph was 7-so I expected the ph to at least drop to 6.5-6.6(I ran another 100 ounces and collected the last 20-----the ph was still reading 7 on the runoff). I understand that the nuts ph rise slowly over the course of 8 hrs but expected the ph off the runoff water to drop closer to the 6.2 with all that flushing that I started with. I'm wondering if my plants are missing out on some nuts that are in the 6.2-6.5 range. Has anyone tested their flush run-off---if so what were the results?

could the soil have a higher ph than the company says?

did this post work?

Everything seems normal here, not sure what you are doing. What you are seeing is the effects of the lime. Lime is a ph stabilizer and keeps the soil near neutral. You are going to have to dump a lot of acidic water through that soil to try and bring it down.

Is this normal?

Yep, hard to beat that soil. You are in great shape!

If I add fresh peat ---say 20-30% vol.---will this bring the ph down or will the lime cont. to stabal. the ph at 7?

I"ve been growing for almost 20 years now and never tested the run-off ph---alwas just the ppm till last night----thanks for the info---never to late to teach an old dog new tricks. thanks again p-----my asian fantasy clones thank you.

DR. VonDankenstine said:

If I add fresh peat ---say 20-30% vol.---will this bring the ph down or will the lime cont. to stabal. the ph at 7?

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The Ph will stay at 7.0 because the lime will still work, but in effect you are removing some lime and replacing it with peat so the lime would quit stabilizing the soil a little sooner. I prefer FoxFarms soil just like it is though, those people know what they are doing. You can visit FoxFarms website and email them and my experience has been that they give an almost immediate response to any questions.

I keep my water at 6.5 for soil and I think that is mostly the ph that hits the plants roots regardless of the soil ph. The lime just keeps me from being stupid and nuting with a ph of 4.0 or something and killing the plants.

I'm an old fart---see we used to believe you dropped the ph to 6.2 befor it hit the soil. Then SLOWLY the ph would rise throu the ph range of all nuts and micro's .That way there would be time for the plant to take in all the nuts. without lock-up.---Don't get me wrong-I do like the FF soils---Just after last night it got me thinking. thanks again

DR. VonDankenstine said:

I'm an old fart---see we used to believe you dropped the ph to 6.2 befor it hit the soil. Then SLOWLY the ph would rise throu the ph range of all nuts and micro's .That way there would be time for the plant to take in all the nuts. without lock-up.---Don't get me wrong-I do like the FF soils---Just after last night it got me thinking. thanks again

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I see, very interesting theory. Makes perfect sense.

('m wondering if my plants are missing out on some nuts that are in the 6.2-6.5 range)
your using nuts?

Here is a chart.

I am using a balanced program of nutes---I wish I had more info on the ph soil---i'm going to send an email to FoxFarm and ask them. and try a few tests on some diff soil...

that is why even thou my soil ph is 7. I should be showing some defec. of iron and maganese but since I have been using a foiliar spray(spray-n-grow) once a week the plants are able to get those micros throu the leaves. So if my theory is right the perfect soil ph for marijuana is 6.6?--just drop your nutes in at 6-6.2.

Picasso-
Talked to foxfarm-Just as you said, the dolomite should stabilize the soil between 6 and 7. With a good flush of 6.0ph(3x container volume/h20) the soil should come down to 6.7 to 6.8 due to salt build-up from nutes. Thanks again

Cool. Good luck.