Ph of runoff in soil grow

Bigby

Well-Known Member
HOWEVER, I do think giving a thorough flushing twice during the cycle is a smart thing to do because you can get unwanted buildup of salts. Again, just my opinion.
I too have been researching similar issues to those raised in this thread. One thing I discovered is that when using organic nutrients (certainly the biobiz range) there are NO salts present, meaning there are none to build up. Thought I'd share as it feels relevant to this thread.
 

WyoGrow

Active Member
First off you here people mention Flushing, and or watering, till you get run off. Is this really good ????? How do you test runoff etc, flushing my plants will rid my buds from the snap crackle and pop from nutrients inside it,

Flushing should be a last resort in any case when to flush , over fertilizing your plant causes you to flush your medium , reading your plant is KEY. Excessive salt build up in your medium all nutrients in time crystallize into some form of Salt , learn feeding schedules and amounts to add So plant can absorb 99 percent of the nutrients your giving it

Watering plant so you get runoff, we need to understand a few things going on under soil and our root system when watering this way we actually take away some crucial elements needed for roots most importantly Oxygen why do you here the craze for Air pots just that holes all around plant to allow better oxygen to the root zone when watering and drenching your soil it compacts and believe it or not it takes away the oxygen thus slowing overall growth .
so keep that in mind next time you water its better to water less more frequently then its to drench your pot

Testing runoff: and knowing whats going on in your soil your going to need a Ph tester and PPM meter , catch tray
to accurately test your run off you need to flush your medium with 4 - 8 times your pot size lets lets start
break up your soil making sure theres no direct open areas where water will pour right out
now slowly start pouring water once you notice it coming out first initial runoff is discarded you want the middle of your flush more or less keep catching runoff testing ph / ppm
you will notice if you got low ph - your ppm will be high as ph comes back into range your ppm will drop flush till your back in PH range thats about it but remember now that soils drenched plant is going into slow growth period till it balances back
more or less osmosis but thats another subject lol

PS: hope this helps
Your take on watering and it depriving the root of oxygen is almost completely contrary to everything I have read, been taught and/or experienced myself. Now soil compaction facilitated by watering can and will smother roots. But that is in poorly structured high clay soils. And in this case it smothers the roots by not allowing the water to pass through the soil at a rate that will draw fresh air in behind it as it descends through the soil. Good growing mediums generally have good enough structure with components like perlite and sand to prevent heavy soil compaction. Soil drenching to the point of runoff is about the only way to get good air turnover in large planting containers. Not to mention prevents dry pockets in the growing medium that encourages salt buildup that can ultimately damage roots growing neat the dry area int he medium. Good soil structure is key though. If you have poorly structured, highly compactable soil then I agree. A large one time watering is harmful because it will compact the soil and not run off, becoming stagnant.
 

Panda NYC

New Member
The runoff water is the final PH of the water absorbed by your plant. A lot of people find it less problematic because many cannabis plants have the capacity to grow between PH of 4.5 to 8.5 - this does not mean the plant is at its best. The best PH of runoff water should be between 5.6 to 6.
 

hydroMD

Well-Known Member
@ Greenlikemoney - if the runoff "quickly went from top of soil to side of pot to bottom of pot to out the weep holes" then what makes the PH change so much? Test your runoff PH and see if yours does too. I would almost bet that it does. I think it's pretty logical to believe that if the soil has some salt buildup, or is overly acidic, when you pour water through it the Ph would change as it comes out the bottom. But everyones soil has fertilizer in it. So how much change is ok? What if it went from 6.5 to 4.0 - would you still not worry? Maybe your plants aren't showing a defficiency, but perhaps they COULD grow better if the Ph of your soil were adjusted slightly? Would it be worth it to check the runoff Ph then? I still don't know the answer... just cause for debate. If you end up doing any research on the issue and find something that might be useful, post it up. I would love to read it.
I would be foolish to dispute your post, but for me it's simple. Giving your plants solutions that are properly Ph'd and then flushing once or twice during the cycle is enough.

Thats just me, everyone should do whatever they feel they need to do to maximize their plants health.[/QUOTE]


If your watering fast enough to send water cascading down the sides of your pot your doing it wrong!!!

Soak the top layer of soil, leaving it sit for 10 min, then water. Soil will absorb the water instead of draining down the sides.

Also, if your plant has a problem then check your runoff and adjust a little. If things look fine then your ph isn't swinging fast enough to negatively affect the plant.

To say measuring runoff is useless is ridiculous. Plenty of info to be gathered to help isolate defeciencies
 

hydroMD

Well-Known Member
First off you here people mention Flushing, and or watering, till you get run off. Is this really good ????? How do you test runoff etc, flushing my plants will rid my buds from the snap crackle and pop from nutrients inside it,

Flushing should be a last resort in any case when to flush , over fertilizing your plant causes you to flush your medium , reading your plant is KEY. Excessive salt build up in your medium all nutrients in time crystallize into some form of Salt , learn feeding schedules and amounts to add So plant can absorb 99 percent of the nutrients your giving it

Watering plant so you get runoff, we need to understand a few things going on under soil and our root system when watering this way we actually take away some crucial elements needed for roots most importantly Oxygen why do you here the craze for Air pots just that holes all around plant to allow better oxygen to the root zone when watering and drenching your soil it compacts and believe it or not it takes away the oxygen thus slowing overall growth .
so keep that in mind next time you water its better to water less more frequently then its to drench your pot

Testing runoff: and knowing whats going on in your soil your going to need a Ph tester and PPM meter , catch tray
to accurately test your run off you need to flush your medium with 4 - 8 times your pot size lets lets start
break up your soil making sure theres no direct open areas where water will pour right out
now slowly start pouring water once you notice it coming out first initial runoff is discarded you want the middle of your flush more or less keep catching runoff testing ph / ppm
you will notice if you got low ph - your ppm will be high as ph comes back into range your ppm will drop flush till your back in PH range thats about it but remember now that soils drenched plant is going into slow growth period till it balances back
more or less osmosis but thats another subject lol

PS: hope this helps


Lol.... ok


First off, if you do not have runoff you need to cut your ppm being added in half. Second, 4-8 times pot size for flushing?!?!?!?! Way overkill.

3x pot size is all ya need with 10-20% nute mix. (Adding low ppms helps break down accumilated salts, like using oil based products to clean oil based stains)

Also... testing your runoff when adding 8x your container size gives you ZERO info... only a washed out reading. The first 10ml-30ml runoffper gallon container size is what you want to test. ( 5 gal pot = 50-150 ml) give your pot a small pre soak to get the top layer of soil wet before u try to test to make sure your water is running through your soil.
 

hydroMD

Well-Known Member
Is there any good reason to test the Ph of your runoff in a soil grow? I know it's good to check when u flush to make sure it's the same coming out as it was going in. But what does the Ph of your runoff really tell you during a normal feeding or watering? I did a plain water last time, and just to kill my curiosity, I tested the runoff. The water I put in was 6.4, and my runoff was 5.5- does that indicate a problem or is it perfectly normal? I was guessing that my ruin off would have a higher Ph, but had nothing to base that on... It was simply a guess, and obviously a bad one. If anyone could take the time to explain this for me I would really appreciate it. I put it in advanced section because I figured you Guys would be the ones with most factual based answers.
Roots organics will be low after watering and should slowly creep back up as it dries. If you start seeing defeciencies then adjust your ph a few points and wait a week to see results
 

Panda NYC

New Member
Also I like to add some more insights, in case a lot of people go around and try to change the PH of their soil when it isn't necessary.

First of, no reason to change the soil when runoff water PH is at 5.5 - it's a very good PH level. You only need to be alerted when the runoff water PH is less than 5 or higher than 7.5.

Also if you are using organic fertilizers, the runoff water PH level matters less, because the nutrients are in a more complex form of compounds. The plant must decompose them before the using them during photosynthesis and respiration - therefore the level of charged ions will modified during the process of decomposition (usually to a mild and more plant-friendly level).

Now, have you wondered why we recommend to water at PH of 5.6 to 6.0 for hydroponic growing and at PH of 6.2 to 6.5 for soil? You guess it right, because in a hydroponic environment, the PH level of the water will not change much after watering. The pH of pure water is related to the relative number of hydrogen and hydroxyl ions. If water has a higher proportion of hydrogen ions, it is acidic and has a pH less than 7. If it has a higher number of hydroxyl ions, then it is alkaline and has a pH of greater than 7. But water doesn't naturally exist without other mineral ions being present. In a soil environment, there are many free uncharged elements around, so they will take up the number of hydrogen or hydroxyl ions to form new chemical compounds - and these new compounds may be helpful or harmful to the plant depending on the original chemical compounds.

When then original chemical compounds are simple compounds - usually found in non-organic nutrients like "GH bloom," etc, the PH level of runoff water represent an overall "helpfulness" of the new compounds absorbed by the plant. Therefore a PH level of 5.6 to 6.0 is optimal to the plant.

That being said, PH level does not represent everything. You can have a very harmful environment while the PH level is optimal, while you can also have a very helpful environment while the PH level is very acidic or alkaline. BUT, if you want to take less risk, it's good to keep the PH level at optimal.
 

Panda NYC

New Member
Finally, the run-off water's PH level might not represent the overall PH level of the water being absorbed by the plant. This is because many chemical compounds will be flushed to the bottom of the pot after watering, therefore forming a particularly strong acidic or alkaline environment. The plant might be absorbing perfectly PH balanced water from other part of the soil in the pot, while the run-off water shows sign of significant acidic or alkaline level.
 

Zzyphr

Active Member
@MDEVA
Ran across this old thread while searching this exact question. In my case, the plant is showing signs of distress. I decided to check the outgoing and it was horribly low. Extreme measures are begining to show progress. For me, checking the outflow pH let you know what the plant is taking from the soil and nutrients administered. So if you have a baseline early, then you can get a coarse understanding if the plant needs more nutrients, not less - as well as maintaining soil pH.
One negative outcome is the quicker destruction of your pH sensor, but such are the costs of a wonderful hobby.

@ Dr. Greener
Voice of reason and respect. Thank you.
 

cannakis

Well-Known Member
Checking runoff pH is alot like staring into the toilet bowl after a good dump. It's not really indicative of what you ate. Pay attention to what goes in, not what comes out. And like the toilet, a good flushing every now and then seems to help.
That's not necessarily true... Because different characteristics of your bowel movements Do indicate too little or too much of certain nutrients... And you can definitely see that fake yellow corn.
 

cannakis

Well-Known Member
Jesus... Reading plant runoff tells you nothing!

:: shakes head ::

P-
How can you say that? There is definitely Something to be said about the runoff, it can tell certain things, its not like you are testing something completely different, it still pertains to that specific plant and pot.
 

Nullis

Moderator
It tells you more than nothing but less than everything, which for most intents and purposes happens to be just more than enough.

By which I mean it certainly can be interpreted as providing some clue that things aren't wildly out of whack. Provided that you water slowly, know the pH of the water source (ideally its near neutral), and discard the first oz or two of the runoff.
 

cannakis

Well-Known Member
It tells you more than nothing but less than everything, which for most intents and purposes happens to be just more than enough.

By which I mean it certainly can be interpreted as providing some clue that things aren't wildly out of whack. Provided that you water slowly, know the pH of the water source (ideally its near neutral), and discard the first oz or two of the runoff.
exactly
 
Is there any good reason to test the Ph of your runoff in a soil grow? I know it's good to check when u flush to make sure it's the same coming out as it was going in.

Aright so peep this shitz... i made the mistake of NOT checking my run off ph and almost lost my biggest momma.. u want the ph going in to be the same coming out.. the problems won't show at first but acidic soil will ruin your crop.. I've had to flush my momma 3 times.. fully .. had done a partial flush like 3 gal to see what would happen , and it instantaneously showed bounce back, so a few days later and did a 9 gal flush, yer supposed to flush 3 time the volume of the pot.. .. if the ph drops alot after putting in nutes to runoff.. flush, .. nothing wrong with flushing the shit outta her.. got a shake the bottles of water to help oxiginate and cleanse and feed all at the same time, black strap mollasses will assist the rizosphere in the uptake of nutes..and keeps good bacteria in the soil also.. maintain a nice warm soil temp, water with warm water.. a little cooler than hand temp.. check ph every time u water, water to 20% runoff . If u don't it will build up and become acidic which will lead to lockout and the loss of your crop.. ph is very important.. o agree that if it looks fine it probably is.. but how closely are u inspecting? What's hunidity? I went to a mix of fox farm happy frog and ocean Forrest. . It's a soil less Peet moss and earthworm casting perlite and vermiculite .. pre Nuted... but u must check ph bro.. must check everything .. always. if u give her an inch she will take a mile .. in both directions but u gotta be dedicated. . If u feel it, it's probly real.. get her done bro u will be fine. Ps. U must check yer ph.. and get away from "dirt"use spikes media.. makes a world of difference .
Is there any good reason to test the Ph of your runoff in a soil grow? I know it's good to check when u flush to make sure it's the same coming out as it was going in. But what does the Ph of your runoff really tell you during a normal feeding or watering? I did a plain water last time, and just to kill my curiosity, I tested the runoff. The water I put in was 6.4, and my runoff was 5.5- does that indicate a problem or is it perfectly normal? I was guessing that my ruin off would have a higher Ph, but had nothing to base that on... It was simply a guess, and obviously a bad one. If anyone could take the time to explain this for me I would really appreciate it. I put it in advanced section because I figured you Guys would be the ones with most factual based answers.
 

Rrog

Well-Known Member
Firstly, adding "nutes," regardless of the label immediately puts the whole natural plant / microbe relationship into question.

Secondly, if the aforementioned relationship is allowed to happen, the plant and microbes determine the soil pH, regardless of your "pH balancing" the water. Measuring pH can be fun, but not necessary.

If someone's bottle-feeding plants, and using some sorta soil as a grow medium, then maybe there would be value in measuring pH. This is sort of a hybrid soil / hydro thing. No idea what's going on in there
 

greasemonkeymann

Well-Known Member
Jesus... Reading plant runoff tells you nothing!

:: shakes head ::

P-
thank you!!!
ANNNNND
How can you say that? There is definitely Something to be said about the runoff, it can tell certain things, its not like you are testing something completely different, it still pertains to that specific plant and pot.
No.
If you are into flushing, salts, ppms, and PH, you should check out the whole growing with chemicals thing.
if you have even 50% of the grasp on organics you won't need a ph tester at all.
And flushing?
I won't even dignify that one with a response.
might as well be buying superthrive and carb boosters to go with your 0-50-50 bloom ferts
 

cannakis

Well-Known Member
thank you!!!
ANNNNND

No.
If you are into flushing, salts, ppms, and PH, you should check out the whole growing with chemicals thing.
if you have even 50% of the grasp on organics you won't need a ph tester at all.
And flushing?
I won't even dignify that one with a response.
might as well be buying superthrive and carb boosters to go with your 0-50-50 bloom ferts
Haha did I even say flushing? Again I have to disagree that pH does matter... But also agree that I Should Have Fucking Listened! Haha but I have learned more than I ever thought from said foolishness.!

Speaking of... I'm losing girls left and right because I top them to clone the seed stock and they have like No leaves except 4fans and the nodes, and I water too much sometimes thinking I didn't, and kill it! And my clones are taking forever!!!

Haha honestly I think it was is due to my "pH"ing the water which fresh rain water by adding ACV and I think I should have left it alone! Man I'm a fool.!. I always think I can reinvent the wheel, and want Everyone to know "my" opinion.!
 

greasemonkeymann

Well-Known Member
Haha did I even say flushing? Again I have to disagree that pH does matter... But also agree that I Should Have Fucking Listened! Haha but I have learned more than I ever thought from said foolishness.!

Speaking of... I'm losing girls left and right because I top them to clone the seed stock and they have like No leaves except 4fans and the nodes, and I water too much sometimes thinking I didn't, and kill it! And my clones are taking forever!!!

Haha honestly I think it was is due to my "pH"ing the water which fresh rain water by adding ACV and I think I should have left it alone! Man I'm a fool.!. I always think I can reinvent the wheel, and want Everyone to know "my" opinion.!
ahhh man, gotta love ya brother.
I don't know what to say man
 
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