Ph of runoff in soil grow

MDEVA

Active 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.
 

Drampire

Active Member
Not so sure about PH. Mine always seems to come out around 5.5 with roots organic putting 6.3-6.7 in from veg to bloom. I just pay more attention to the ph going in, and ppm coming out to see if I need to flush.
 

Deuce&Reg

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.
yes it is important to know your run off ph. there is a reason why your ph is coming out almost a full 1.0 lower than its goin in. soil is too acidic. testing your runoff is just about the easiest way to test your soil ph. but the main question is how do your plants look? are they showing a ph problem? or any problem at all or do they look healthy? dolomite lime is what you should ammend your soil with to bring up the ph. it has a neutral ph. considering its like $10 i believe for a 40lb bag cost isnt an issue and it will last forever. i have ran into same issue with roots organic and after top dressing with the dolomite it eventually climbed its way back up. easiest solution for you tho man, go coco lol. it doesnt have its own ph its neutral like the dolomite meaning the only thing your plant gets is what you feed it and it eliminates the whole soil ph issue. i switched and never looked back....lol
have fun and be safe!:weed:

deuces
 

MDEVA

Active Member
Well, I've received two COMPLETELY DIFFERENT answers. Doesn't seem to be a middle ground on the issue given the responses I've received thus far. I just tested runoff again tonight... The Ph going in was 6.3, the Ph coming out was 5.3. My plants don't seen to be showing any Ph related issues, or any issues for that matter. I do however think that Duece&Reg has a valid argument for saying runoff is important to check, but would like to hear more opinions ifanyone would like to help out. I wish I had some time to do proper research on the issue. If someone has a link to an article on the subject post it in this thread!
 

MDEVA

Active Member
Well holy Shit Batman! It took me all of 30 second to find this link. This video makes a very good point about why the Ph SHOULD drop about
3/4 - 1 whole point when u test the runoff. I don't know what Sieve&Reg background is like, but this video was posted by the"medical marijuana academy" whoever the hell they are. Oh, I know thus is off topic, but I read an incredible thread on here about "main-lining"... I thought it was referring to shooting up so I almost didn't read it. You guys should check it out. Just search main lining on RIU.


VIDEO REGARDING THE PH OF RUNOFF IN SOIL. http://m.youtube.com/#/watch?desktop_uri=/watch?v=8lBYuGlvRNA&v=8lBYuGlvRNA&gl=US
 

MDEVA

Active Member
http://www.kindgreenbuds.com/marijuana-grow-guide/measuring-ph-of-soil-runoff.html

That article kind of acknowledges Duece&Reg's point. Basically to some it up, it says to test just the first few drops of runoff $ out should have dropped about half a point. If it goes beyond that, soil is too acidic, and line or other supplement needs to be added to adjust Ph level of soil. I guess going by that logic, it's safe to assume if your runoff is higher than what u put in, you should add something to liter Ph of soil?
 

greenlikemoney

Well-Known Member
Ok, let's examine this. ( I'm assuming you are growing in pots BTW ).

You have plants, growing in soil, in pots. When the plants become dry and need feeding or watering, look at the situation closely. The soil has contracted away from the pot.
Then you water/feed. The soil starts absorbing BUT, before it expands to meet the pot, you have runoff that has quickly went from top of soil to side of pot to bottom of pot to out the weep holes.

Now, what exactly does that runoff tell you?

IMHO, nothing. If your plants are healthy, why worry about something like that.

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.
 

MDEVA

Active Member
I think the PH of your runoff HAS to tell you SOMETHING, I'm just still trying to find the right answer. Both of the sources above make great points, but they differ in their opinions. One says 1/2 point drop is ok, the other says up to a whole point difference is normal. I am going to do more research when I have time so I can try to find a more concrete answer.

@ 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.
 

l8lDANKl8l

Active 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.


You need to add dolomitic lime for a natural ph adjustment. Most all GOOD ORGANIC soils have this. Like my local nursery mix and the happy frog mix i blend together.

Run off is 6.5 all day after i add a ton of worm and bat poo, and other stuff.

Heres my soil mix; im using liquid fertilizers though. Its called the G.O. (general organics) box from General Hydroponics. They are all organic; all of them except for processed squid(doesnt make tent stink) are vegan too so its all organic for sure which makes the smell absolutely amazing. Im in veg and i can tell you right now what each plant will be by the smell; i cant wait to smell the flowers mmm:)

Coolest part about this mix is its soooo hard to burn plants. Im growing some very good strains(blue cheese,lemon kush, blueberry, etc) but all bag seed mixed up so not sure whats what and im feeding all of them every 5 days with VIGOROUS growth and NO burn signs whatsoever. This setup is very easy, had very good results(smell and growth) and on top of that its the cheapest stuff when comparing price to return benefits.

Hope this helps you out

  • 2 parts local nursery mix(canadian sphagnum peat, gypsum, dolomitic limestone and perlite)
    1 part happy frog potting soil (contents and %'s should be able to be found online)
    1/2 part earthworm castings ("wiggle worm" soil builder)
    1/2 part Jamaican Bat guano
    Also add a little extra chunky perlite to ensure the roots have something sturdy to hold onto






 

T.H.Cammo

Well-Known Member
I think the writing's on th wall! Not only is it common to see noobie questions (like this one) here in the Advanced forum. But now clueless noobies are also giving thier (absolutely wrong) advice here as well. You'd think that they would be smart enough to keep thier mouthes shut if they didn't have the proper knowledge - but no they go ahead and say whatever comes to mind. Unless the Mods do something to get RIU back on track it might just be time to think about moving on down the road! I've seen quite a few discontented posts lately.
 

DrGreener

New 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
 

dank smoker420

Well-Known Member
if you are trying to find out the soil ph i would not test the run-off water it can be an inaccurate way of testing. get a soil probe. there about 15-20 dollars. and will tell you the exact ph of the soil.
 

l8lDANKl8l

Active Member
I think the writing's on th wall! Not only is it common to see noobie questions (like this one) here in the Advanced forum. But now clueless noobies are also giving thier (absolutely wrong) advice here as well. You'd think that they would be smart enough to keep thier mouthes shut if they didn't have the proper knowledge - but no they go ahead and say whatever comes to mind. Unless the Mods do something to get RIU back on track it might just be time to think about moving on down the road! I've seen quite a few discontented posts lately.

theres nothing wrong with anyone expressing anything. If they are wrong and they keep their mouth shut how can anyone ever tell them otherwise? i think all input offered from anyone is worth SOMETHING. whether it be that you learn what to do or what NOT to do, etc.
 

Haydoon

Well-Known Member
I think the writing's on th wall! Not only is it common to see noobie questions (like this one) here in the Advanced forum. But now clueless noobies are also giving thier (absolutely wrong) advice here as well. You'd think that they would be smart enough to keep thier mouthes shut if they didn't have the proper knowledge - but no they go ahead and say whatever comes to mind. Unless the Mods do something to get RIU back on track it might just be time to think about moving on down the road! I've seen quite a few discontented posts lately.
So what was your answer then? I'd love to hear it as it must be correct and as well thought out and delivered as DrGreener. Cant wait :shock:
 

greenlikemoney

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.[/QUOTE]

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.
 

greenlikemoney

Well-Known Member
Thanks Hay.....I just don't see a need to complicate growing a weed, especially if the person growing is growing small and for personal use. I've seen people spend thousands on set-ups, equipment, zillions of nutes and plant enhancers etc etc. They most likely will never break even on their investment. To me that seems foolish. It's one thing to care about your plants and want to maximize your yields and quality. It's a whole different scenario when the stress of growing a weed overshadows the joy of growing that same weed.

that's just my opinion
 

MDEVA

Active Member
WOW. It's been a while since I checked on this one. I thought this part of one of my posts had pretty much summed up the reason that I ever put this thread out in the 1st place - "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." GOD DAMN why does T.H.Cocksucker always have to prove he's so fucking superior to ANYONE who asks a question? Maybe this isn't the forum for me. YES I'm only growing a couple of plants for personal use - but for some reason I didn't realize that made me the biggest fucking lowlife "noob" the internet had ever seen. I joined this site so I could take advantage of info provided by people who have been doing this a lot longer and more successfully than myself. I didn't come on here to argue with a bunch of people who have God Complexes. Here's a fucking suggestion - if a thread, or a particular post, bothers you so much you feel the need to shit all over a person who's simply searching for information, and playing devils advocate in order to have something better explained, then do the world a favor and go fuck yourself to death.

Yes - I'm on what I consider my 1st actual grow. That's why I've read damn near every "sticky" I could find, and spent hours looking at different grow room setups, and browsed reviews on products I'm using. My plan all along for this first grow was to stick to the basics. I haven't done anything other than to feed and water my plants, monitor temp & humidity, control the light schedule. I have paid special attention each time I feed to stay within Ph ranges reccommended for soil, and PPM appropriate for the stage she is at. I don't know what even prompted me to check the Ph of my run-off. I guess I had the pen sitting next to me while I was watering and became curious. I tried looking the answer up myself. And after getting so much conflicting information from various sites I decided to pose the question on this forum. Maybe it would help some of the crybabies on here if I say sorry.... so open your ears and put on your glasses T.H.Cum-guzzler "I'm SORRY for having a question so absurd it would actually make you consider taking your condescending remarks and leaving R.I.U. for good."

@ Dr. Greener - Thank you for your response. I appreciate the time you took to add constructive feedback. So in the future when I water, it's not necessary to keep going until I see a little bit of water in the saucer underneath? I usually rake around the top 1/4" or so of soil, and then start pouring very slowly pausing ever so often to give the water/nutrients time to moisten the soil and then continue pouring until I see the first small amount of water in my tray. Usually there is approx 1/4"-1/2" water in the bottom after everything drains thru that has to be dumped. The whole process takes me maybe 20 minutes or so. I didn't know this was an unhealthy practice. I really am thankful for the advice.

@ Greenlikemoney - I get great personal enjoyment out of growing my "small personal amount." You're right though - I WON'T EVER break even on my "investment." Maybe that's because I didn't see getting into growing an "investment" in the first place. I'm not growing to save money. I'm not growing to make money. I have no plans to sell anything I grow to recoup the funds spent on materials. This is purely a hobby for me. I hope it's ok with you that I still care how my plants turn out though.

I still don't see anything wrong with the question I asked. I put it in the section of RIU where I believed I could get the most informed responses. I thought maybe this was one of those things that should be checked periodically to ensure my soil was healthy and didn't have any Ph related issues. After reading such negative comments, I'm glad it's nearly harvest time for me because I would hate to think of another question that might upset the likes of T.H.Cunt.
 
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