Soil very acidic near stalk but normal everywhere else.

The soil in this pot is very acidic around the rootball/stalk area, like a 4 on the scale, but the soil on the outside of the pot is all testing within normal ranges. My plants seem to be showing signs of nutrient burn and/or lockout. I believe I overfed my plants with liquid nutrients that eventually threw off my soil pH and is now causing some kind of lock out issues. When I check the area next to the stalk it’s comes back very acidic but when I test the outer edges it comes back within completely normal range.

Has anyone experienced something like this? How should I go about fixing this? My plan is to top dress Dolomite Lime around the stalk. I was also thinking about baking soda because it supposably works faster.

The plants are about 2-4 weeks into flower.

Any information or personal experiences is much appreciated.

If its locked out you may need to flush some ph'd water through it to rinse the salt build up. Then feed a light feed.

I'm struggling with this currently the pH is low at the bottom. 4.5 or so after a flush. This particular grow is FoxFarm with chip limestone mixed in. I've been doing 1/2 miracle grow high N during veg with half well/half rain. Well water hard water and full of magnesium carbonate same as the chip limestone.

So decided to start trying and using clear ammonia in the water to raise the pH as the 1/2 strength veg nutes took it down to 6 or so from 7 out of the faucet. Takes about a teaspoon to bring it back to 7, another to take it up to the high 7s near 8.0.

I'm also using some dissolved limestone in the water.

I'm convinced I'm just using too much fert. And I need to add a layer of the limestone to the bottom of the pot when initially filling as well as mix some in with the soil.. This will always stay at 7.0 until it's dissolved. And this is where the roots end up bunched.

Live and learn, I have two in flower and they are 4.5 at the bottom. Flushed them with 20 gallons of water and still low. Only three weeks left so only some limestone water for the rest of the time.

Potassium bicarbonate is a fast acting safe for plants pH raiser recommended for potted soil. Sodium bicarbonate will harm it I bet.

What do your plants look like. Why did you test pH in both places. I also wonder does the low pH near the stalk matter there are few roots in that area