Differing Ph levels.

[Renaissance Redneck]

Hydrated lime can be used to raise pH pretty fast, Cerul, but it's caustic and tricky to get the right dose. If you don't mind, I'm gonna ask some of my Uber Soil friends what they would recommend.
Have you tested the pH of the materials you used in your mix?
If you're pH is that far off, starting over with a different soil may be the best option. Let me give a shout, before we get too crazy

 

[A4]

I believe the scaling on your meter is off. If I were guessing I would say your pen is not capable of two point calibration? If that is the case you are probably only able to do a single point 7.01 cal. This works if you are measuring water or liquids that will fall in around the neutral range but not too well for acids or bases. So it reads correctly in the neutral range but since we have nothing to calibrate it against in the acidic range then it is basically guessing. It would be nice to take a known solution and check it against the meter. Wine, beer or orange juice should fall in around 4.0-4.5. Try and test one of those liquids and see if you meter is reading properly. I would recommend a hannah 98129 in the future when you have the extra money. It is a very nice meter with a longevity and quality which doesn't break the bank.

In order for your soil to be at 2.0 it would need to be very acidic, like the inside of a lemon acidic. I am not saying it isn't low but I don't believe it is that low. There isn't much you can do to raise your soil that much without hurting the plant's roots. Honestly, I can't imagine your soil being that low though, I have never seen anything below low 5's and I use ultra hot soil. One thing that will cause your readings to skew is dry soil. As soil dries, the acidity goes up because buffers only work in an aqueous environment, in other words, you need water for your buffers in the soil to work. You can expect about a point difference in dry soil and moist soil.

If it were me, I would 1) make sure your pH is truly that low. If you are absolutely positive it is well below being able to repair without a lot of chemicals then go to 2.
2) I would transplant. When the soil is moist, gently scoop well around the outside of the plant and deep enough to make sure you go below the roots of the plant. From the looks of that plant, 12" would be deep enough. Take the entire ball of soil and move it to soil that you are sure falls in the safe range and just water the plant through until the roots grow into the new soil.

 

[Cerul]

Thanks for your reply and suggestions A4.
My Milwaukee Ph pen came with a pouch of Ph 7 calibrating solution. The pen consistently gives me a 7.0 reading in this solution.

I'm not sure how the soil I'm using got so acidic but I'm going to get a new bag, perhaps Foxfarm next and transplant my seedling. Hopefully this will kickstart new growth and I won't end up losing the plant.

 

[Waira]

Red, A4, thanks mates for helping!... Cerul, this is well sorted from what I've read,...that estimated pH has just gotta be wrong, the plant would not even be alive if it were anywhere near that pH,... a mass nutrient lock-out would have happened way sooner, at there'd be symptoms of all kinds by the time you got into the low 5's - high 4's,... very likely the soil is acidic, but not that badly! Also, avoid FuxFarms soils, they too have been found to be frequently overly acidic,... bags of OF and HF have been testing in the low 5's!! ...are you in the USA? And can you get to a good horticultural supply store? Let us know what you can find locally, and we'll see about recommendations....

 

[Renaissance Redneck]

I believe the scaling on your meter is off. If I were guessing I would say your pen is not capable of two point calibration?

My Milwaukee Ph pen came with a pouch of Ph 7 calibrating solution. The pen consistently gives me a 7.0 reading in this solution.

I think that's what A4 is saying, Cerul. A good pen should have two, even three calibration points. Two is minimum, usually with a 7.0 and a 4.1. That ensures your meter is scaling properly.

Red, A4, thanks mates for helping!

A4 nailed it.... he's a frickin stud!

 

[oldster]

Morning RR,

I did calibrate my pen and store it in a calibrated solution of Ph 7. I make sure between each test to wash the probe tip and dip it in the calibrated solution to make sure it is consistent.
So I did a couple of tests each time when I felt the soil had dried out. The first time I watered with a Ph of 8.0 and the runoff came to 5.2. So the soil Ph would come 2.8. I waited for the soil to dry out again and this time watered with a Ph of 10.0 and the runoff came to 6.1. This time the soil Ph came to 2.2.
I hope I'm running the calculations right.

Hi Cerul, I can't see any way that your soil pH could be 2.0 that is the level of a very strong acid.

One possibility is the fact that you are storing it in calibrating solution. Probe storage solution is potassium chloride, KCL not sure what your calibration solution is but if it is not KCL it could effect the chemical composition of the liquid in the probe.

Another possibility is that you are using RO or distilled water which would have no buffering ability. Only tiny additions of anything to it will cause big pH swings that can just as quickly go the other direction with very little additional input.

If you have access to "Hard Water" I would give that a try as the calcium carbonate in it acts as a great buffer.

Last possibility is that your probe is messed up

 

[Cerul]

Thanks for all your input Waira, RR & oldster.
After dicking around with the soil and pH runoff I think my soil pH may have been around 4.7 and not in the 2's. You guys are right, nothing can grow in that. I store my probe in regular tap water adjusted to 7.0 and I also have calibration solution that I use to cross test and verify.
My plant is doing a little better after I switched soils. I bought a new bag of seedling mix and re-potted it. It hasn't grown taller but it has sprouted a few more leaves in the last 4 days. Still growing slowly but I have hope. She is at day 20. She is a New York city Diesel auto from the Pyramid seed co. that I bought from the Attitude seed bank in the UK.

 

[Duggy]

Hi Cerul.. the plant looks nice and healthy... everything seems under control now..

 

[Renaissance Redneck]

I store my probe in regular tap water adjusted to 7.0

Just a word of caution, storing your meter in tap water will shorten its life and degrade its accuracy. Storage fluid is made with deionized water, potassium chloride and other good stuff to keep the electrode bulb from clogging with minerals. It's cheap, and a bottle goes a long, long way.
I did misspeak earlier, I use 7.0 and 4.01 to calibrate.
Just sayin'....

It hasn't grown taller but it has sprouted a few more leaves in the last 4 days. Still growing slowly but I have hope.

Grow karma coming your way, CerulIt can be amazing how they bounce back.

 

[Cerul]

Thanks Duggy & RR.

Damn! I'm going to buy some more calibration solution ASAP! Who knew growing shit would need so many accessories!
Why do you need both the 7.0 & 4.01 solns RR?

Also I noticed a bunch of flying insects around my plants...Fungus gnats I think. They look like fruit flies. I bought some Grow Safe brand garden insect spray but i'm not sure its working. Its been 1 day after spraying the mofos but they're still there. I grow indoors and there's not 1 ant or cockroach in my apt. (I know because I'm quite the slob) but all of a sudden where did these fungus gnats come from???? Anyway the plants look ok so not concerned too much. I'll keep spraying once a day......