so i am attempting to grow organically my mix is made up of 33%promix 25% compost manure 20% perlite plus bone meal ,bat guano,and some other organic goodies i plan on water only and topdressing so far my plants look fine they are just entering veg from the seedling stage and are in 10 gallon pots QUESTION IS i am using dechlorinated tap water this time and my ph is over 7 or right at 7 from my tap should i worry about lowering it before i water? i did add some dolomite to my soil mix just a little any answers will be appreciated! oh yeah 18% EWC
I'd let it cycle for 3-4 weeks and run a soil slurry test to check the mediums starting pH. If it's within range you should be fine with your tap waters pH. Your promix should have already been pH balanced. So adding more lime and bone meal may push your pH higher than you want it to be.
you may know that the actual soil fixes the ph, but if you screw it every time you water then thats a very pissed plant, I'd go check your local mall or home depot, wallmart for the water vending machines, the water is stable at 6.5 and is R.O so you will need to add a pinch of mg or calmag you may re check the ph with a pool strip test $5.00 from your swim pool cleaner or drugstore good luck
i always went that route using walmart water every grow but it is starting to get expensive and laborous so i decided just to try my tap i do fill a small tub and let it sit a couple days maybe i will do 1 plant with only walmart water and see if there is a difference i have 2 clones that i can use for the experiment
Find a water report for your tap water and compare it to this chart. https://extension.psu.edu/interpreting-irrigation-water-tests pH of your water is pretty insignificant. Alkalinity, hardness, and salinity are the ones to really make sure of. Testing your starting pH like Tim mentioned is also a good idea. RD
For what it’s worth I just moved across the country and compared my water to the same chart. Took me less than a minute but I’m well versed on the numbers already. Good to go over here. If your shower heads clog up or if it’s difficult to get soap off your hands it’s a general indicator you could have problems long term. If you’re comfortable giving a general location this could also be helpful if you’re unable to easily access a report. RD
that is my plan so if i am using store bought RO water with a ph around 7 i should use ph down? or what is the norm for an organic grow?
Your soil should correct the pH for your plant to up take nutrients. That's why that pen I showed is nice to have, takes all the wondering out of it. But I always pH my water to 6.5 for soil.
It's a bit misleading that our microbiology will adjust our soil pH or even adding copious amounts of organic matter will adjust our pH. Soil microbes have the ability to make slight changes near the root tip. Organic matter will buffer our pH some. Both have an impact on our pH. But, neither will bring a highly acidic or alkaline soil back into a neutral pH range. The addition of bicarbonates from our water can lead to a build up in our medium. I run an organic no till mix. I use well water that I know is high in total alkalinity, near 200 ppm. I can run 3 cycles in a 10 gallon pot. Then I'll experience iron lockout due to high growing medium pH. The microbes won't help and neither does the addition of the worm casting several times per cycle.
This article explains things a bit better and adds some more insight on how pH affects soil microbiology and fungal communities. https://www.nature.com/articles/ismej201058#:~:text=Soil pH has a strong,for example, Lauber et al.