I had problem of low pH level, I added more nutrient rich potting soil, it buffers the pH effectively.

Caelian

Is your pH test potentially inaccurate? Or your lime not mixed well enough?

It takes a while for the lime to alter the pH. The pH will definitely go up over time. Not too much to worry about though because the plants will get their nutrition from your fertigation water which you can make any pH you want. My tap water is 8.0, and I add a teaspoon of vinegar to each 2 gallons and it brings the pH down to about rainwater levels.

Sorry, but I just noticed that you used hydrated lime. Dolomitic/garden lime is suggested, not hydrated lime. Hydrated lime is too fine and powerful and might burn the plants, but if you mixed it in throughly you should be ok. Hydrated lime should work faster too. Just be careful with it.

This post was edited by edweather on Mon, Jul 29, 13 at 9:46

Twice the recommended amount of hydrated Lime? Yikes, that sounds like disaster...although I don't have personal experience. I'd start over.

Good catch, Ed.

Josh

I recently tested the pH of my 5:1:1 using the pour-through method. It was just under 5.0. To counter the high alkalinity of my water, I add acid to it. My trees--pawpaws-- in one gallon containers are thriving in this mix. Like many trees, pawpaws are acid-loving. Are you sure you need to raise the pH to make your plants happy?

Marc