I’m having yellow leaves week 1 of flower I test my ph run off at 7.5 when I water I water at 6.5- 6
- Thread starter doeboi24
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Capn-Crunch
Well-Known Member
I agree, it sounds like an N issue, but no pics to go on.
My soil is 6.7, but I PH everything to 6.2 - 6.4
Dr. Who
Well-Known Member
Not!
Low N issue's start at the top and work down
This is a high P issue!
List me what your feeding and how much (Brand of feed too).
What media are you in and what feeding schedule are you using?
What water source?
What is the feed solution pH?....When you use it...
I would ask for 2 pictures please.
1 of the whole plant and one of the new growth...
pH of the run off is simply the run off pH, and is NOT a good way to meter soil pH, not at all!!!
I want to know what VEG feeding you did and give me the answer to that in relation to my first 2 questions above also.
Classic high P issue!
WingAK
Well-Known Member
The way nitrogen deficiency starts is it begins from the bottom of the plant and works its way up through the stems and branches. According to Penn State University.
You may have noticed some of the lower leaves a pale green to yellow color.
This is a sign of a lack of nitrogen with your marijuana plants. Not sure where you’re getting your information but it’s wrong and adding bs to water to lower or raise the ph while growing in soil is absolutely wrong I have had more plants look like they have deficiency’s and it was simple the ph solution killing my plants.
pulpoinspace
Well-Known Member
could be n or another mobile nutrient or it could be pH it depends what medium you're in, what nutrients you're using. pics and more info would help. but if you're not feeding your plant u gotta feed it.
JayBio420
Well-Known Member
You are 100% incorrect. Nitrogen is a mobile nutrient and when required at the top for new growth, it is transferred from the bottom, thus the older growth showing the deficiency.
OP, if your run off is more alkaline than your water, you have alkaline agents in your soil I would think. Usually runoff is the starting water adjusted by whatever is in your soil. A high soil pH may be causing issues with nitrogen, see image attached.
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xtsho
Well-Known Member
Skip the soil runoff pH. Different things runoff at different rates and have different pH levels. Checking soil runoff pH is a new thing that is unnecessary. In the decades I've been growing the only thing I pH is hydro and coco. Even then all I do is either keep the reservoir at the proper pH or pH the solution if watering drain to waste. I've never checked runoff pH.
I never even heard of checking runoff pH in soil until just a couple years ago on this forum. Now it seems everyone is doing it. If you want to check soil pH do a slurry test.
I see too many people chasing soil runoff pH and flushing their plants, pH'ing to extremes to get the runoff to the level they want, etc...
I think @Dr. Who has pointed you in the right direction. What have you been feeding it? More is not always better.
I never even heard of checking runoff pH in soil until just a couple years ago on this forum. Now it seems everyone is doing it. If you want to check soil pH do a slurry test.
I see too many people chasing soil runoff pH and flushing their plants, pH'ing to extremes to get the runoff to the level they want, etc...
I think @Dr. Who has pointed you in the right direction. What have you been feeding it? More is not always better.
JayBio420
Well-Known Member
Can one of you guys talking about his issue being high Phosphorus explain what you mean? I can’t find any online references to high P yellowing bottom leaves nor in my books. I did find references to high P manifesting as deficiencies in zinc, calcium, magnesium, iron or copper, with zinc being the most common (Cervantes, 2006).
A zinc deficiency shows chlorosis of new and younger leaves, not old bottom leaves... so I’m puzzled where your information comes from.
Without anymore info, this is classic nitrogen deficiency. My guess is the plant is using it to fuel the stretch.
As for run-off pH being a new thing.. new to you I guess! It is useful to me as an indicator of what’s happening in the soil, and I can list references from sources if you’re curious about the topic. Soil slurry pH and soil probes are sketchy at best as they don’t really give you a good sample size. And it’s not a homogenous mixture.
A zinc deficiency shows chlorosis of new and younger leaves, not old bottom leaves... so I’m puzzled where your information comes from.
Without anymore info, this is classic nitrogen deficiency. My guess is the plant is using it to fuel the stretch.
As for run-off pH being a new thing.. new to you I guess! It is useful to me as an indicator of what’s happening in the soil, and I can list references from sources if you’re curious about the topic. Soil slurry pH and soil probes are sketchy at best as they don’t really give you a good sample size. And it’s not a homogenous mixture.
Dr. Who
Well-Known Member
Yeah screwed the pooch on N def expression but he's not got an N issue of it's starting bloom (increasing N now will not help much, too late)......I still watch my tops or upper plant for N def if I want to correct..(Guess I run too many N sensitive strains) ...Habit sometimes trumps my schooling. Still, low N is easy to see from real light green coloring, graduated in the whole plant.
As far as Cervantes goes. I gotta giggle a bit here, sorry.
Books can be nice tools. Yet he and others, limit what they say in books to what actual real world issues look like and are. How really old is that first publication? At that time, had he seen issues from nutrient charting that have come about by our time now? He's working on his experience from what he feeds.....At the time that book was written. He was well versed in Jack's classic and maybe a few others in the 3 part style of use. Also, bet you dimes to dollars he did not use the charting, for those "3 parts." He calculated the NPK values that he wanted to apply to his plants!
Now then. In bloom when you get early yellowing of the leaves (starts with stem leaves) that progress up and then out branching.
This is a sure sign of using too much P. P acts like a ripening agent, when you use too much. It acts like one with out too much....
Many (far to many) nutrient makers drop N and increase P way to much! The high P is making the plant think it's closer to finish then it is...Others will still use far to much P but, elevate the N to "mask" the high P. This elevated N is not good either, and still the lower leaves yellow faster then they should! Organic growers believe that green to the end is better but, yes, we get natural color shifts near the end time.. That's the key here - near the end!
Still, it's easy to see a low N situation as it's being expressed in the whole plant as too light a color green in a variable way, bottom to top or top to bottom. NOT a sudden yellow out of the lower leaves and quick progression up the plant.
It's not the lack of N but, the high P doing the work here. The real reason is poor nutrient feed charting and the makers jumping on the band wagon of "more is better" advertising and unneeded levels of P&K because they do this or that....
The makers of Dyna Grow defied the market trend and did not make stand alone grow and bloom products for some years (can you actually remember that far back?). Then, due to falling sales due to the other makers hype on how great the stand alone products - with their gee whizz boosters make your grow increase in (insert what ever stupid claim you know here). That they buckled and added a stand alone nutrient line....The CEO made a statement to that and wished they didn't have to make that leap.
FOLIAGE PRO does everything start to finish......So does a few Jack's products and they are STILL very popular.....Let me have you open that Jorge book again.. Now look at some of the picture credits.. One of the names should stand out to you,, if your worth your salt.....Guess what he use's? Still today.....Jack's,,,period!
Easy peasy cure to the problem is to simply run your veg nutrient for 2 weeks and then start the Bloom nutrient. Sometimes this still ends in a situation that some think is too early a yellowing/color change in the plant.
I find most nutrient lines to over use P and some at almost a criminal rate.
"Boosting" P&K out side of a nutrient line that actually employs one in their line...Not a great idea. Some lines that do, way overdo it.....I'll endorse Canna, and Hesi as being lines that use a "booster" effectively, AND chart for it correctly! Adding more N at this point? Too late and adversely effects THC production.
Yet it should be noted that high K and Mg levels will reduce THC production too. Might add some K and Mg but, as a sulfate and at rates not effecting that issue...I'm after that S...
Anyway, You can see this problem in the Plant Issues section at this site all together too much..Hell, Ben used to preach the same thing to the choir! "You don't have low N. Just stop bloom foods with high P." I got tired of the section for the same damn thing over and over...
As far as run off pH being a good way to test soil pH...I cry BULL SHIT!
#1: Soil drops and rises in pH as it's wet to dry. At what point in this swing did we water again? How much of a variable has now played into your run off pH from this FACT?
#2: Now to the big point on this run off pH and soil thing....
Soils self pH's! Unless your in-going solutions are over 8.0 or under 5.0......Who cares? The soil will self correct....
Soil has a basic pH when built, We add forms of Ca for buffering and for the plant.... As the soil cooks.. It's settling in on a pH that will change once a plant hits it.
That's right, the plant in the soil helps set the soil pH to where the plant stain likes it....This is part of the soil food web of organics
Now we learned that when you water. The soil drops in pH and this can be over a whole point...As the soil dries back out. It rise's back to it's resting point.
So, it's easy to see that over watering will, eventually, cause a pH issue.
The same is true for watering with a too high/low pH solution as it can, and will overpower the buffer in the soil in time. Can be quicker then some think.
So run off metering be new to me? Not at all and NOT accepted by me at all. Too many damn variables...NO organic grower worth his salt will ever care about soil pH - If he built his soil right!
BTW, I organic farm. Have for ever, Ran greenhouses and a massive Yew farm for cancer drug production (till they figured out how to "grow" the chemical faster and cheaper in a test tube.)
No soil grower should ever rely on run off pH and any math formula to be near as accurate as a proper meter. The industrial standard of HANNAH HI98168 or the HI99121 direct soil meters. I Guarantee your not metering with a .002 accuracy! Not that you need to but, we have both on the farm for field testing...
I have heard of a $129 HANNAH soil probed meter doing well. I can't fully endorse it, because I haven't tried it. Yet some of the good words are from some I trust...
I have one in my grow (99121) and I bought a liquid probe and recalibrated for that as I test solutions in-going and ignore "soil" pH.....YES, even for synthetic runs...SOIL, SELF pH's!
JayBio420
Well-Known Member
So, you try and pick apart a reference I gave, and I can give many more. Then you tell me that my reference is too old (2006), yet your growing experience of decades is accurate? I could go on to list four books I own, and a half dozen websites instantly that confirms what I have suggested, none for your advice. A bunch of anecdotal evidence, as per usual on this forum. Twist people’s words, shoot down their references, provide none of your own and then call bullshit. You say soil pH isn’t important, then go on to say how it can change and what soil pH meter you support. Pick a side of the fence guy, you confuse people spouting bibles of your own unsubstantiated anecdotal BS. As soon as you realize you got called out, you write a dictionary to sound smart.
Soil pH rises and drops as we water... you ask when we are checking it? OBVIOUSLY you check soil run off when it is wet, because it was watered. And I didn’t say I RELY on run off pH. I don’t even take run off PH so button it up old man.
I take year breaks from this forum because old hippies think they know everything and desseminate wrong info, like telling a guy with yellowing old leaves he has a high P issue.
I feel bad for the beginners that listen to this shit.
Soil pH rises and drops as we water... you ask when we are checking it? OBVIOUSLY you check soil run off when it is wet, because it was watered. And I didn’t say I RELY on run off pH. I don’t even take run off PH so button it up old man.
I take year breaks from this forum because old hippies think they know everything and desseminate wrong info, like telling a guy with yellowing old leaves he has a high P issue.
I feel bad for the beginners that listen to this shit.
Capn-Crunch
Well-Known Member
"Soils have the capacity to resist changes in pH, but there are instances where the water pH can cause changes. Both the soil and the water contain negatively and positively charged ions that influence the chemical composition and thus the pH of soil. Some soils are more resistant to change, while other types can change rapidly if the water pH is significantly different from the soil matrix."
Actuosity
Well-Known Member
Seeing as the ol hippies post is full of great information and not trying to defame anyone maybe you should take longer breaks, the forums would appreciate it.
Personally I don't test my run off, just leads to issues and confusing yourself. I just water at the correct PH.
JayBio420
Well-Known Member
Soil contains residual alkalinity. Residual alkalinity will affect your run off . Buffering capacity of compounds will also affect resulting run off pH.An inference can be made of the state of your soil by reading run off pH. If you don’t believe that, that’s fine, but it’s a thing.
JayBio420
Well-Known Member
It’s full of run on bullshit, that he can’t and won’t reference, and you can go kick rocks. You will be seeing me around, and you don’t speak for anyone but yourself.
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madvillian420
Well-Known Member
Do you guys use digital PH meters or the old school vial/drops to check your water/nutes pre application?
RIKNSTEIN
Well-Known Member
Are you in soil with nutrients" Or are you in Organics? Don't worry about PH coming out, only worry about what's going in. I run my PH @ 6.3 so as it raises, it runs through all the levels for maximum nutrient uptake.
