• 🎅 Early Christmas Sale - 25% Off All Seeds 🎄
    Use Coupon Code At Checkout: XMAS25

why are my leaves turning?

2,408
263
going in or coming out?
I mean is that the ph of the nutrient solution before you give it to the plant, or the ph of the runoff coming out of the pot after you water.

But I gather you are using one of those cheap ph meters you stick in the soil. Those things are not to be trusted. Only way to truely know is test the nutrient solution on both ends with a proper calibrated ph meter. Anything else is just guessing.
 
1,159
263
But I gather you are using one of those cheap ph meters you stick in the soil. Those things are not to be trusted. Only way to truely know is test the nutrient solution on both ends with a proper calibrated ph meter. Anything else is just guessing.
I wouldn't use the meter to measure solution pH, but I find they are reliable (agree with other tests) in soil if used correctly. If I act on what they say, my plants improve. You have to use them in moist soil, and leave them in the ground for a couple mins, to get an accurate reading.

In my experience, nutrient solution and water pH doesn't change soil pH, and soil pH can overwhelm the solution pH.
 
Is that the ph going in or coming out? Either way thats not great. And ppm? What are you feeding?
Pine bark is also very acidic and will throw the ph of the nutrient solution out of whack . You want ph going in between 6-6.5 and coming out the same.

I scraped off the pine mulch, flushed the plants and caught water coming out. I tested it with my meter I use on clone water and it read 6.59.
 
Man the Ph should be 5.5-6.5 max and I lean way more on the 5.5 side or as someone else said it’s locking them out, flush them for a bit with water and a lower Ph like 3 days then reintroduce nutes.
 
179
63
Pine bark when it starts composting will sequester Nitrogen. This looks like what was happening.

Pine bark needs to compost for several YEARS before any benefit is found in the soil.

What happens is the microbes use nitrogen to help with the composting process, locking it up in that process and the plants are unable to get enough N to grow properly if at all. Good that you scraped it off.

It wood eventually starve the plant.
 
2,337
263
Man the Ph should be 5.5-6.5 max and I lean way more on the 5.5 side or as someone else said it’s locking them out, flush them for a bit with water and a lower Ph like 3 days then reintroduce nutes.
I wouldn't recommend you didn't do any of the above. You've gotten good info previously in this thread, stick with it for best result op
 
2,337
263
I wouldn't recommend you didn't do any of the above. You've gotten good info previously in this thread, stick with it for best result op
Oops I just noticed my autocorrect typo!

I tried to say I would recommend you don't do anything suggested in the post 6 above, which I was referring to initially

5.5 is a disaster for plants in soil and you never flush a plant for 3 days in a row, I wouldn't flush your plants anyway, but everything in that post will kill or hurt your plant & quickly
 
Last edited:
Hey everybody, on the high ph soil note, how do you lower ph of soil?

My soil is organic, about 7.0ph and I grow in fabric pots. What’s there to do to lower it to 6.5?

Thanks for your input
 
179
63
Hey everybody, on the high ph soil note, how do you lower ph of soil?

My soil is organic, about 7.0ph and I grow in fabric pots. What’s there to do to lower it to 6.5?

Thanks for your input
Don't worry about soil pH in organic soil. Actually a pH of 7 in soil is the optimal pH. Thats according to all the state extension services that do soil testing in the US. 7pH is optimal. You don't need to fuss over it. Just water and watch the plants grow. You'll be fine.
 
7,251
313
Don't worry about soil pH in organic soil. Actually a pH of 7 in soil is the optimal pH. Thats according to all the state extension services that do soil testing in the US. 7pH is optimal. You don't need to fuss over it. Just water and watch the plants grow. You'll be fine.

This is not true. Different crops require different soil ph. Tomatoes like a little acidic and peppers a little alkaline for example.

Marijuana in soil likes slightly acidic. So like 6.5 ph. Ocean forest potting soil is buffered to 6.5 ph with oyster shell.
 
179
63
Respectfully disagree.

I run no-till and get my soil tested and re-tested.

Started out in 2016 with soil pH of 6 or slightly less.

2019 got soil tested again - same soil only thing grown in it was cannabis and no amendments. Used soil tested @ 7.0pH Which is optimal and why the plants themselves along with the microbes changed the soil pH to where they want it. Thats apparently 7.0pH.

Not trying to be a dick here. You can believe what you will. Plants roots via root exudate along with microbes in the soil CONSTANTY change the soil pH. There's no set pH that the plant wants to see.

Its just science.

If you wanna beat up your plants roots and the micro-organisms go ahead and use pH up/down. You should feel better that you are helping.


BTW I water with RO water and it tests to 6.5pH (not that I test it but I have several times over the years).

Maybe you are talking more about soil acidity/alkalinity instead of pH?? These 2 tests are only reliable done in a lab under lab conditions. Why I get a test done and suggest folks that wanna grow in soil get soil tested.

See the label there where the blue line goes up to the optimum line that = 7 pH - I didn't make that up thats my state extension service telling me that. All the state university extension services will tell you the same thing. They are actual soil scientists working in a soil lab. Food for thought.

2019-08-06 (2).png
2019-08-06 (3).png



Here you can see the original soil test - same soil, only thing done with the soil is grow weed in it over and over organically no-till no fertilizers and no pH adjustments.
I would draw a conclusion that cannabis may not care that much about soil pH as long as its within say 6pH - 7pH with a little play either way.

2016 test - you can see the pH below optimum at 6.2pH
I actually would like it lower like this so that the rock dusts in the soil will break down better with a slightly acidic soil pH. Take note of the ACIDITY test results on each soil test and compare.

As a side note, every successive grow got better and plants got bigger. Which = higher yields.


2019-08-09.png
2019-08-09 (1).png
 
7,251
313
Respectfully disagree.

I run no-till and get my soil tested and re-tested.

Started out in 2016 with soil pH of 6 or slightly less.

2019 got soil tested again - same soil only thing grown in it was cannabis and no amendments. Used soil tested @ 7.0pH Which is optimal and why the plants themselves along with the microbes changed the soil pH to where they want it. Thats apparently 7.0pH.

Not trying to be a dick here. You can believe what you will. Plants roots via root exudate along with microbes in the soil CONSTANTY change the soil pH. There's no set pH that the plant wants to see.

Its just science.

If you wanna beat up your plants roots and the micro-organisms go ahead and use pH up/down. You should feel better that you are helping.


BTW I water with RO water and it tests to 6.5pH (not that I test it but I have several times over the years).

Maybe you are talking more about soil acidity/alkalinity instead of pH?? These 2 tests are only reliable done in a lab under lab conditions. Why I get a test done and suggest folks that wanna grow in soil get soil tested.

See the label there where the blue line goes up to the optimum line that = 7 pH - I didn't make that up thats my state extension service telling me that. All the state university extension services will tell you the same thing. They are actual soil scientists working in a soil lab. Food for thought.

View attachment 887386View attachment 887387


Here you can see the original soil test - same soil, only thing done with the soil is grow weed in it over and over organically no-till no fertilizers and no pH adjustments.
I would draw a conclusion that cannabis may not care that much about soil pH as long as its within say 6pH - 7pH with a little play either way.

2016 test - you can see the pH below optimum at 6.2pH
I actually would like it lower like this so that the rock dusts in the soil will break down better with a slightly acidic soil pH. Take note of the ACIDITY test results on each soil test and compare.

As a side note, every successive grow got better and plants got bigger. Which = higher yields.


View attachment 887388View attachment 887389

The root zone changes all the time. I realize that even with fertilization the soil becomes more acidic and raises as the plants uptake for instance.

But with a fertilization program (and i was talking about container gardening) having the medium buffered to 6.5 to start gives a healthy medium range for the plant to thrive.

And i use well water that is 150 ppm total mineral content and 8.0 ph out of the tap and grow in potting soil. Ocean forest or the like. And never use any ph adjustment. The nutes and the oyster shell or lime buffer in the soil keep it in range. We should know our source water alkalinity and how to manage our medium and how it interacts with our soil amd nutes.

I only use pure blend pro grow once the nutrients in the soil are depleted. But any decent complete balanced fertilizer could work.

But if the ph is allowed to raise to high certain elements may be locked out or just not soluble.


Even pro mix warns to check medium ph to make sure it wasn't “over limed”. As clumps can pass through the screens sometimes. That would raise the ph to 7 and cause problems potentially.


Dont think we are talking about the same thing.
 
909
93
Plants roots via root exudate along with microbes in the soil CONSTANTY change the soil pH. There's no set pH that the plant wants to see.
That's been my experience (although I don't know what's causing it). In actual use, soil doesn't seem to have a static ph (the way it's typically referred to.). It rises as it dries. And, there's different pockets or ranges of ph in the soil. The way I grow, that could be salt buildup due to water not passing through a pocket of soil as much as other areas in the soil (not washing salts away as evenly?). Or, it could be a byproduct of the life in the soil (as you described).

I'm not in organic soil. It's a very light soil which I feed every watering with an organic-leaning fertilizer product (Grow More - Sea Grow). I think I have some soil'ish attributes to what I'm doing. But, I feed every 2-3 days, and don't depend on the soil to supply very much nutrients. I control my soil ph by feeding more or less. If it's above 7 when drier, I just feed more to make the soil more acidic with salts. I monitor the runoff ppms which track the ph pretty good. (That may not apply to all soils, though.).

I haven't ph'ed my nutrients in years. I found the right strength to feed, and it works out. I can vary the ph with stronger/lighter feed.
 
179
63
This is a great discussion.

@MIMedGrower - I grow in containers. The soil test is a mix from all the containers I use. The excess soil from up potting and soil out of rotation are the sources of my soil I got tested. It all makes its way back into growing medium in >30 days. Either starts cuts clones VEG and flower. It all rotates in.

I guess my point was that I don't even think about pH until I see my test and then I don't think about it.

OK wait... how can I make my soil more acidic?
 

Latest Cannabis Seeds

Sundae Cookies
Sold out

Sundae Cookies

Divine Genetics
Sundae Driver x GMO Cookies
12
Feminized
New
$200.00
Sunset Sherbet S1
Sold out

Sunset Sherbet S1

Divine Genetics
Girl Scout Cookies x Pink Panties
12
Feminized
New
$200.00
Strawberry Sorbet
Sold out

Strawberry Sorbet

DNA Genetics
Heirloom Swiss Sativa x Sorbet
6
Feminized
Limited
$85.00
Sorbet Stash
Sold out

Sorbet Stash

DNA Genetics
Headstash x Sorbet
6
Feminized
Limited
$85.00
Top