Adjusting the pH of my soil waterings

[John1961]

Hi folks,

I have a question about PH buffering that I'm hoping someone more knowledgeable than me can answer.

I am growing indoors, in a soil mix of 66% FFOF and 33% perlite. I did not add any lime.

I know that the optimum PH for cannabis is around 6.5 to 6.7. So I've been adjusting the PH of my water going into the pot to around 6.5, thinking this is all I need to do to keep the soil PH in check. The water coming out of the pot is usually under 6.0.

Unfortunately, I think I have the classic symptoms of a nutrient lock-out problem with mid-level leaves going light green and developing rust-colored spots between the veins. I am currently three weeks into flower.

So my thinking is that I need to bump up the PH of my water going into the pot since my soil seems to be dropping the PH by at least a half point or more (based on the runoff PH). In other words, would bumping up my water PH to around 7.0 result in the soil PH (and water run off) to increase to around 6.5 ? Is this method of "PH buffering" a good approach or am I looking at this the wrong way?

Thanks in advance for any advice.

 

[NCDude]

Ok, I'm no expert BUT I have learned this: If you are using soils like Happy Frog, Ocean Forest there is no need to adjust the PH of your water. I threw away my PH meter after speaking to the folks at Fox Farm myself. These soils have dolomite lime in then which buffers the PH levels. My plants have never looked this healthy. In the past, I too thought I had 'nuit lockout', I didn't. Maybe my problem was burn from too much fertilizer. You can always add a dash of lime if you want, it's cheap. I'm not sure, but I don't want to put the PH up & down chemicals in my grows either. Others may tell you different, but I'm a happy camper not fretting about PH anymore. Good luck!

 

[CO Finest]

Buffering means it adjust up and down. Lime is not a buffer as it only adjust one way. Yes 7.0 in ffo works and should come out around 6.5 too 6.6. Now if you see it dropping to low you can do a 7.0 flush to get it back to 6.5 too 6.6. You should always start at 7 and check run off. if it comes out 6.7 then lower ph in too 6.8 and see if run off is 6.5. As soon as you see 6.0 run off with 7.0 going in it is time for flush and you will see it go back up. Some people use lime but for me it becomes a big headache. let the real buffering soil tell you what is going on. Whats nice about doing that is it is way easy to see when you got salt and nute build up and when its time to flush. Lime and mislead you and hurt plant growth if flush is not done when needed if needed. Ffo should have enough nutes for a month or so. In 5-7 gallon pots it can last up to 2 months water only unless using r/o then cal mag needed.

 

[CO Finest]

do not mess with it if it gos from 6.5 -6.6. it is good for it to move a little. That helps with nute uptake.

 

[John1961]

Thanks very much CO, that's the answer I was looking for.

 

[CO Finest]

Your welcome. I wish you the best and if you come across any more ? just ask away. Have a good day..

 

[Greenhouse250]

Ok, I'm no expert BUT I have learned this: If you are using soils like Happy Frog, Ocean Forest there is no need to adjust the PH of your water. I threw away my PH meter after speaking to the folks at Fox Farm myself. These soils have dolomite lime in then which buffers the PH levels. My plants have never looked this healthy. In the past, I too thought I had 'nuit lockout', I didn't. Maybe my problem was burn from too much fertilizer. You can always add a dash of lime if you want, it's cheap. I'm not sure, but I don't want to put the PH up & down chemicals in my grows either. Others may tell you different, but I'm a happy camper not fretting about PH anymore. Good luck!

I agree, been at it for over 5 years and I use lime and never use ph up or down.. make sure your problem is not calcium.

 

[COorganics]

I agree that PH is a non issue in a soil grow, that is PH of water AND PH of media. This may all change if you are using hydro nutes in soil, I have no idea about that. CO'sFinest is skilled in that department and I'm sure he is steering you right. I do think that this whole PH'ing think is one huge canna myth, and one probably born from the use of these bottled nutrients. IMHO, there really is a better way, it's called the soil food web, organic matter, and natures way of doing things. Once again I'll bring up the majestic redwoods. No one is PH'ing their soil, no human is feeding them chelated bottled nutrients, yet they grow tall and mighty and healthy. What's up with that?

 

[Old Guy Teaches]

I PH to 6.1/6.3 and my plants are usually way past 15 feet and super green.....way past. Fox Farm. Felt Pots. water every 4 Days.been doing this a VERY,,,,VERY Long time. Actually I got Busted in 1973 for One Plant. LOL!!!!!!!!!!!!!!!!!!! Fine was $2.300

 

[Brudley]

Ive actually been adding sulfur to lower the ph and lime to keep it in check. The plant benefits from both or suffers with lack of either. Then there is Epsom salts or magnesium sulfate, which the plants can also use. I’m still experimenting myself a with living soil at the moment. I’m looking for water only start to finish.

 

[Nunyabiz]

One of the best ways to stabilize pH is top dress with aged compost and a few pinches of Gypsum.

 

[Old Guy Teaches]

AH....white Widow, Good memories.