Newbie here, to indoors anyways and I have a pH question. First, I never worried about pH because I did everything outdoors. Right now I have a soil mix of perlite, top soil and mushroom compost. Everything is going great and I am 6 weeks in and I just switched to flowering (12/12) cycle. My pH in my soil varies from pot to pot, only a bit, from 6.6-7.0. I bought a soil pH meter to take my measurements. I know that 6.2-6.8 (pH) in soils is optimum for all nutrients to be ready for plant uptake. So, is it a problem to keep my plant at this range? Or should I try to reduce my pH towards 6.2-6.8? If I do need to lower the pH, then could I use lemon juice diluted with water to obtain a lower pH? I plan on going slowly and if it takes a few weeks of figuring it, by using lemon juice, then that is fine with me. Background info: I am using 9 liter pots with 1/4 perlite, 1/8 mushroom compost, and 5/8 top soil. I used Age Old Organics Grow formula (half dosage) every ten days with seaweed extract every week. I only water with Ice Mountain (because my buddy who has been doing indoors for years told me that it is great). I just did a molasses and Cha Ching application (1 1/2 tbsp of molasses and 1 tsp of Cha Ching per gallon) to encourage the change over to the flowering cycle. Let me know.
Properly mixed soils are able to buffer pH on their own. As long as you're not over applying chemical fertilizers, there's no need to monitor/measure/adjust pH. pH is controlled/stabilized by the CEC (Cation Exchange Capacity) of the soil. Same as outdoors... http://www.soilminerals.com/Cation_Exchange_Simplified.htm Aren't you a "breeder" of GMO plants? You should know this.