Soil Too Alkaline > Phosphorous Lockout

I've got an issue that's been developing over the past few days and it's starting to freak me out.

Some of my leaves are turning a DARK green/blue, even grey in spots. They're brittle to the touch as if they've been roasted under a heat lamp, but the buds way up high show no signs of heat stress. The veins on the leaves are brown, it looks like they're dirty.

Growing in a mix of FFOF and ProMix. For nutes I'm using FF Big Bloom. I was going to try to incorporate Humboldts Secret - Flower Stacker (NPK 0-7-5), but opted out at the advice of people here. An issue I've had consistent problems with is alkalinity of my soil.

I'm looking at the symptoms of phosphorous lockout and they seem identical. On top of that I read it can be triggered by soil that is too alkaline or acidic because of the roots' need to be a very certain pH to be able to utilize it.

I've got seabird guano to help with the P issue, but the plant won't even get any of it if I don't make the soil more acidic. Anyone have recommendations for products to help out with this?

I tried looking into Mykos, but it looks like you need to add that to the soil before planting/transplanting. Am I wrong on that?

Why do you think you have an alkalinity problem using the soils you are usin?

I bought a meter a couple weeks ago and it hasn't budged from "Alkaline". Now with these symptoms going on it seemed to add up. Are those meters not reliable? It's one of the three-way ones.

My best guess as to WHY it happened would be residual crap from one of the times I overfed. Can't that alter soil pH?

One of those three-way ones you stick in soil, like to measure if it's dry or damp? Those things are garbage. I had one telling me vinegar was reading 7.5 on the scale.

blake9999 said:

One of those three-way ones you stick in soil, like to measure if it's dry or damp? Those things are garbage. I had one telling me vinegar was reading 7.5 on the scale.

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Hahaha! Why am I not surprised? So what do you guys suggest for monitoring? Just one of the soil pH test kits?

That would be your best bet. Those Ph meters aren't very accurate for soil measuring.

Good news. Picked up a test kit and the soil is right around 6. Thanks for the heads up on the crap meter. Figured it'd be off - had no idea it'd that off.

It was due for a watering which probably compounded the phosphorus issue. Fed with a small amount of the Big Bloom, and a while later added about 1tsp of seabird guano in a 1/2 gallon of water and gave it that. The brittle leaves are starting to feel "alive" again, obviously the worst aren't coming back.

Are the brown-veined, dirty looking leaves going to get their color back, or is the damage permanent?