Cal Mag Low Soil PH

Good morning everyone.
I have been battling this low PH in my soil being a beginner and assuming Oceans Farm would buffer correctly ( last time I assume lol) I fell victim to my first issue.
I made a post a week or two ago and was recommended to use Dolomite Lime. I put some in water and poured in and then top dressed / watered.
It has brought my PH up slightly but not high enough or fast enough. I also flushed before doing this and it didn’t seem to help much.
My girls are doing amazing for the most part but at least half of my leaves are yellowing and rust spots.
I also used Recharge a week ago and today as well.

My question is, is there anything I can do to have quicker results? My guess was a Cal Mag issue because my PH in soil from runoff was in low to mid 5s even though I put 6.5 in.
So to recap the main issue plant is oceans farm soil, feeding jacks 321 to 20% runoff. 3 gallon pots watering / feeding every 2 days 1 gallon. PH in always 6.5 and runoff ph is low 5s. Put probably 2 tablespoons of dolomite lime prilled top dressed / raked in and watered.
I am guessing I just have to wait it out but my leaves look so bad :frowning: I hate seeing my girls suffer
Temps are 75-80 and humidity 45% running 20/4 with DLI around 40-45 and lots of airflow etc.
PPMs were around 800-1000 out but since adding the dolomite lime it’s hard to get accurate reading since it is skewing my #s higher.
Any other info needed just ask, hopefully someone can put my mind at ease or help me lol. Posted few pics so you can see different parts of the issue on different leaves.





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Plants are 52ish days from popping out of soil and are blue dream autos.

PPMs in was 1150 and out 1500. Assuming part of that is the dolomite lime but leading up to adding the lime runoff always 800-1000

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Yup gotta wait it out. The damaged leaves wont recover but the spread should stop.

Jacks is a calcium based nutrient with epsom salt for magnesium. So it shouldn’t be short of cal or mag. But the calmag dosage is a good call.

I wouldnt add more dol lime just yet. Give her sometime to try to straighten out. By next watering, the pH should be a tad higher

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I might have asked this before but have you done a soil slurry? Runoff is useful to track but it can be misleading. Plenty of threads here with people chasing runoff ph. @PurpNGold74 is right it will take time for the lime…hahaha that rhymes.

Ive been using FF for over a year now, course I also use FF nutes. Prolly work better together. Ph never been an actual issue…I got a bag of lime my first grow…only used 1 tblsp of it because soil slurry showed buffers working just fine.

Where do you buy your soil? I find that if I buy it from a place that stores it inside not outside the soil is better.

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Im on round 4ish with some pots. Its been 2-3 years lol. I did buy some extra soil and mix it all together for a bit of a ‘recharge’. But for the most part it holds steady for me as well.

I found out about the dolomite lime after i mixed my own soil prior to finding ILGM. That batch had to be in the low 4’s it was so imbalanced :man_facepalming:t5::rofl:

This is a great point! My nurseries keep customer soil inside. Maybe a diff maker

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Yea and I cannot do I lt due to my roots being everywhere. Also the other 2 plants that have perfect runoff PH are fine and only the one with low PH is bad so I’m going to assume the readings are correct. I got my soil from Amazon and I’m staying far away from oceans farm from here on out because there’s way too many post with same issue I’m having.

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Also I’m hoping the recharge does it’s thing. According to the creator PH isn’t an issue if using it because of the microbes so between the lime and Recharge I’m hoping it fixes it over time just wanted a quicker fix

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Ok.

I didnt realise you had 3 plants in the same pot. Sorry.

I use Recharge and Tribus and pH is kinda moot between the two. I still like to adjust it a bit if its around 5 or lower. But they definitely get the job done.

Just a waiting game now my friend. Give her time to process and adjust

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3 plants all with different soil only the oceans farm is the issue:( happy frog and random mix are reading good)

How does this stop you?

The roots are spread all throughout the top. I can’t dig into it without hitting roots. It’s impossible to get 2in down or further without hurting the roots ( I tried when putting the lime in)

Good stuff from Brother Purp. While they resemble each very closely I’m leaning towards a phosphorus deficiency. Correct me if I’m wrong @PurpNGold74 :love_you_gesture: I usually see this more in this stage of flower versus calcium especially with jacks 321

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Thats actually a good guess. The P deficiency would continue to spread regardless of pH, as it wasnt addressd. If it keeps getting worse, boost the ,i believe, part A?

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Whatever I need to add I will definitely do I just wasn’t sure. I’ve been doing the standard jacks measurements per 1 gallon

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Here’s a zoomed out view of the plant.

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I also have Bergman’s nutes I haven’t used but I did see the seedling nutes has high phosphorus just throwing that out there if you guys think it might be phosphorus.

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Trying not to add any mud to this conversation, but I’m using Gaia Green nutes. When I started my plants I added 3 Tbsp of the 4-4-4 All Purpose and 1 Tbsp of the 2-8-4 Bloom. Then at the beginning of this month (July 4 weekend) I top dressed all of the plants with 2 Tbsp of the 4-4-4 and 2 Tbsp of the 2-8-4. Next month, They will get 1 Tbsp of the 4-4-4 and 3 of the 2-8-4. This is a pre-planned feed schedule that, in addition to some other stuff (i.e. Alfalfa Meal, Kelp Meal, Bat Guano, and worm castings), were initially added to the Coco/Perlite mix. There is also a single Tea brew that can be fed to the plants around week 6-7 that is supposed to really help with refreshing the grow media right around the middle of the plant’s lives. This is all assuming you’re growing Autos. The Gaia Green nutes by themselves are slow-release, so feeding them monthly helps them keep getting the nutrition they need, along with Cal-Mag Plus treated rainwater. Just my $0.02 from an also newbie grower.

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Appreciate that confirmation Brother Purp, hard to tell early with these 2 versus the long term where the P Deficiency is obvious :love_you_gesture:

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Thats not going to hurt your plant.

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