pH issue resolution

I've had this Plink (Pinkberry x Blue Dream) going great from reg seeds, currently day 21 flower.


Medium; FFHF + FFOF + perlite + dolo lime + mycos powder (see below).
1 gallon plastic pot (Yep, too small, but a bit of an experiment as well.)
Fox Farm Trio nutrient line; Big Bloom, Grow Big, Tiger Bloom.
Down to Earth Root Growth Enhancer (11 species of mycorrhizal fungi and humic acids.) Used as a rapid rooter soak when the seeds went in, and used during transplants.
Hydro Organics Cal n Mag Used every other/few feedings, mixed with nutes or with waterings.
Dyna Gro Protekt (silica) Like what its done for stems and branches. Used as foiliar throughout veg, and mixed with nutes.
Ful-Power (fulvic acid) Used as foiliar throughout veg and mixed with nutes. Really liked this foliar in combo with Kelp and Protekt.
Epsom Salt (Magnesium) Used once mixed with nutes 1 week into flower.
Age Old Organics Kelp (seaweed) Primarily used as foliar with the fulvic in veg, but also applied to soil a few times.

Grown under 2-3x 23w CFLs in a [5 gal] Space Bucket from seed to solo cup size. Then up potted to 1 gallon pot and moved into my 2ft x 2ft x 3ft tent running two cheap-CN 100w COB LED, one with a reflector only and another with reflector and lens. I payed attention to lux during early veg and moved the lamps far enough away to avoid puting too much heat into canopy. Drove LEDs at 40-55w each in veg, likely too hard for these chips, but I was a noob, and thats why I'm learning! Vegged for 54 days.

Anyway, ~6 days after the flower switch, I decided to add/power on the cheap-CN 180w multi spec UFO LED. Temps have been too high for the last week (86-88*F max...in winter..), and I've turned the UFO off again, and will likely remove it and just utilize the 2 COBs to cover the plant from now until I can install my 4x B3590 array.


Back onto the plant. The last few days its been showing discoloration and paling/yellowing. I have kept track of ph in and out for every watering/feeding. I have been having low ph since mid/late veg. I've added dolo lime to a couple feedings/waterings now, as well as top dressing the soil before hand. I'm having a hard time keeping ph in check, and I'm aware thats an issue w/ these peat based soils..I'll be cutting my next batch with cocoa and more perlite I think.


So, I know my ph has been low (and I've been trying to fix it), but the plant has continued to thrive and look very healthy up until this point. Is it finally showing signs this much later? Is it a lack of nutes? I have done two feedings with Tiger Bloom, but at less than rec. dosage. I also speculate the 180w UFO (too much intensity?) caused some of this..its produced similar issues on past plants..another reason its off and getting pulled out of the tent. It may work fine if it had a potentiometer to control its light out put, or if I had more vertical space, but it doesn't and I don't.

The solution? I watered yesterday with 6.4 ph'd tap (dechlorinated for 2+ days), run off was 5.96 ph. The feed before that was 6.46, and the reading before that 5.84. So its been swinging around, and mostly on the low side for quite a while. I see a 5.6 ph on day 7f. =\ Do I no-ph tap water again to try to bring ph back up before I apply nutes again?


>> Full album here << (along with some other projects, scroll down to see the flowering plant)
The pics may not show it well enough, but most of the older leaves are a bit pale/yellowing, from center of leaf outward?

On the plus side, I was rubbing stem/branches some and there is a ton of blue and berry smell in there.

Well, going to get into Jorge's book for some reading now! Hope I have adequate details.....

vahpor said:

The solution? I watered yesterday with 6.4 ph'd tap (dechlorinated for 2+ days), run off was 5.96 ph. The feed before that was 6.46, and the reading before that 5.84. So its been swinging around, and mostly on the low side for quite a while. I see a 5.6 ph on day 7f. =\ Do I no-ph tap water again to try to bring ph back up before I apply nutes again?

Click to expand...

What is the TDS/PPM of your tap water? Often it's too high. My tap water is 600-700ppm. I don't even feed that high. When I started growing, nothing worked until I started using RO water (I mix it with tap to get 150ppm. I call that "water". I add about 200-400ppm in nutrients.).

Your plants don't look like you have that severe of a tap water problem. They look good.

Do you let your soil dry completely between waterings? The soil's ph will rise a full point as it dries. If you're trying to "correct a ph problem" and are too aggressive flushing and feeding tap water only, that will be like holding the soil ph lower because it doesn't get as dry as it could(?)

I spent $60 on a Control Wizard Accurate 8 soil ph probe. That was a very useful investment. It gives me insight into my soil's ph (which is usually a problem due to salt buildup, feeding too strong and/or not enough runoff.). It's nice to see what the ph looks like a day or three after watering. (If you buy one, use the scouring pad to burnish the probe surface before each use. Leave the probe in the soil 10 minutes to get consistent readings. When the scouring pad wears out, use #0000 steel wool.).

I struggled through a similar problem a couple years ago. I switched nutrients, started using an LED (a couple other variables). I wasn't sure what the problem was. I thought it was acid soil. I used hydrated lime (strong and caustic) to "shock" the soil (which is *not* adviseable, but for me it helped). I also thought it was the LED. I later concluded I was overfeeding. I reduced the strength and mixed more (for more runoff each feeding). No problems.

I measure the ppms of my runoff, not the ph. What I've found is that when it reaches 2000ppm I need to start being careful. 2200 is the danger zone. 2500 is when signs of lockout occur. If I see it rising to that level I do half-strength nutes with 50% runoff. (But, I don't even watch it much any more. I know how much works for me. But, the ppms were the key for me. Not ph. Ph was just a byproduct of the runoff ppm being too high due to salt buildup.).

considering that FFOF and HF both have ferts, why are you giving so much extra stuff? do you understand that if you have pH issues, the most likely reason is going to be the fert in the soil? are you sure that pH is the problem? pH is just an effect of fert's action in the soil. stop the ferts and the foliar feeding. it appears that you have done enough already.

az2000 said:

What is the TDS/PPM of your tap water? Often it's too high. My tap water is 600-700ppm. I don't even feed that high. When I started growing, nothing worked until I started using RO water (I mix it with tap to get 150ppm. I call that "water". I add about 200-400ppm in nutrients.).

Click to expand...

Excellent! Now will come the twits saying you don't need to worry about it.

vahpor said:

I've had this Plink (Pinkberry x Blue Dream) going great from reg seeds, currently day 21 flower.

Medium; FFHF + FFOF + perlite + dolo lime + mycos powder (see below).
1 gallon plastic pot (Yep, too small, but a bit of an experiment as well.)
Fox Farm Trio nutrient line; Big Bloom, Grow Big, Tiger Bloom.
Down to Earth Root Growth Enhancer (11 species of mycorrhizal fungi and humic acids.) Used as a rapid rooter soak when the seeds went in, and used during transplants.
Hydro Organics Cal n Mag Used every other/few feedings, mixed with nutes or with waterings.
Dyna Gro Protekt (silica) Like what its done for stems and branches. Used as foiliar throughout veg, and mixed with nutes.
Ful-Power (fulvic acid) Used as foiliar throughout veg and mixed with nutes. Really liked this foliar in combo with Kelp and Protekt.
Epsom Salt (Magnesium) Used once mixed with nutes 1 week into flower.
Age Old Organics Kelp (seaweed) Primarily used as foliar with the fulvic in veg, but also applied to soil a few times.

Grown under 2-3x 23w CFLs in a [5 gal] Space Bucket from seed to solo cup size. Then up potted to 1 gallon pot and moved into my 2ft x 2ft x 3ft tent running two cheap-CN 100w COB LED, one with a reflector only and another with reflector and lens. I payed attention to lux during early veg and moved the lamps far enough away to avoid puting too much heat into canopy. Drove LEDs at 40-55w each in veg, likely too hard for these chips, but I was a noob, and thats why I'm learning! Vegged for 54 days.
Anyway, ~6 days after the flower switch, I decided to add/power on the cheap-CN 180w multi spec UFO LED. Temps have been too high for the last week (86-88*F max...in winter..), and I've turned the UFO off again, and will likely remove it and just utilize the 2 COBs to cover the plant from now until I can install my 4x B3590 array.

Back onto the plant. The last few days its been showing discoloration and paling/yellowing. I have kept track of ph in and out for every watering/feeding. I have been having low ph since mid/late veg. I've added dolo lime to a couple feedings/waterings now, as well as top dressing the soil before hand. I'm having a hard time keeping ph in check, and I'm aware thats an issue w/ these peat based soils..I'll be cutting my next batch with cocoa and more perlite I think.

So, I know my ph has been low (and I've been trying to fix it), but the plant has continued to thrive and look very healthy up until this point. Is it finally showing signs this much later? Is it a lack of nutes? I have done two feedings with Tiger Bloom, but at less than rec. dosage. I also speculate the 180w UFO (too much intensity?) caused some of this..its produced similar issues on past plants..another reason its off and getting pulled out of the tent. It may work fine if it had a potentiometer to control its light out put, or if I had more vertical space, but it doesn't and I don't.

The solution? I watered yesterday with 6.4 ph'd tap (dechlorinated for 2+ days), run off was 5.96 ph. The feed before that was 6.46, and the reading before that 5.84. So its been swinging around, and mostly on the low side for quite a while. I see a 5.6 ph on day 7f. =\ Do I no-ph tap water again to try to bring ph back up before I apply nutes again?

>> Full album here << (along with some other projects, scroll down to see the flowering plant)
The pics may not show it well enough, but most of the older leaves are a bit pale/yellowing, from center of leaf outward?

On the plus side, I was rubbing stem/branches some and there is a ton of blue and berry smell in there.

Well, going to get into Jorge's book for some reading now! Hope I have adequate details.....

Click to expand...

It looks like Nitrogen and a magnesium deficiency to me caused by low ph. If your ph is too low, your plant can't uptake N and Mg (plus others). I had yellowing tops in pre-flower and could not figure out why. Ended up that my ph pen was off and the ph was in the low 5's. I corrected it to 6.0 (hydro) and the yellowing went away within a day. Based on what you are saying and based on the ph chart for cannabis, that's what I'm guessing.

It's over fert. if you enlarge the pic you can see how the leaf tips are turning brown.

az2000 said:

What is the TDS/PPM of your tap water? Often it's too high. My tap water is 600-700ppm. I don't even feed that high. When I started growing, nothing worked until I started using RO water (I mix it with tap to get 150ppm. I call that "water". I add about 200-400ppm in nutrients.).

Your plants don't look like you have that severe of a tap water problem. They look good.

Do you let your soil dry completely between waterings? The soil's ph will rise a full point as it dries. If you're trying to "correct a ph problem" and are too aggressive flushing and feeding tap water only, that will be like holding the soil ph lower because it doesn't get as dry as it could(?)

I spent $60 on a Control Wizard Accurate 8 soil ph probe. That was a very useful investment. It gives me insight into my soil's ph (which is usually a problem due to salt buildup, feeding too strong and/or not enough runoff.). It's nice to see what the ph looks like a day or three after watering. (If you buy one, use the scouring pad to burnish the probe surface before each use. Leave the probe in the soil 10 minutes to get consistent readings. When the scouring pad wears out, use #0000 steel wool.).

I struggled through a similar problem a couple years ago. I switched nutrients, started using an LED (a couple other variables). I wasn't sure what the problem was. I thought it was acid soil. I used hydrated lime (strong and caustic) to "shock" the soil (which is *not* adviseable, but for me it helped). I also thought it was the LED. I later concluded I was overfeeding. I reduced the strength and mixed more (for more runoff each feeding). No problems.

I measure the ppms of my runoff, not the ph. What I've found is that when it reaches 2000ppm I need to start being careful. 2200 is the danger zone. 2500 is when signs of lockout occur. If I see it rising to that level I do half-strength nutes with 50% runoff. (But, I don't even watch it much any more. I know how much works for me. But, the ppms were the key for me. Not ph. Ph was just a byproduct of the runoff ppm being too high due to salt buildup.).

Click to expand...

My tap water is crunchy too.

Yeah just gotta love some of the crazy answers around here!
It's not over ferted!
Blackforest is close !!!!

It does start with what you amended with for pH stability...You need some more. Use Oystershell (powdered) for the added amounts...Add more Myco's at the soil build too!

Now then. By your pH measurements. I say your problem is Ca, Mg and P blocking by overall too low a pH swing at watering..

For the rest of this run (till you fix the buffers in the next) water with water/nute mix that is no lower then 7.0! Higher to 7.5 will be good.
You see, soil pH swings down by like a whole point when you water and as the soil dries back out it swings BACK up to the soils pH value it runs at.....under 6.5 those nutrients - Ca, Mg and P have a limited uptake to NO uptake (lockout condition)....Your getting that by the pH of your waterings being too low, The buffer being too light and the microbes working as hard as they can but not supported enough by the other facts....more can help some but, not enough....

Try what I say for the rest of this run and see I'm RIGHT!
Then adjust your soil for the NEXT run like I suggested...

Grow happy

Doc

Thanks for the replies all!

I am awaiting arrival ph calibration solution, as well as EC solution.

My ppm readings, using the cheapo TDS-3 meter. I'm not sure what scale it functions on. But, some of my recent ppm readings from run off are:

11-29 1320ppm (tap water, which is in the ~160ppm range)
11-27 1360 (feed of 790ppm)
11-24 -no data- (water)
11-22 1860 (feed 1410)
11-20 1570 (water)
11-18 1860 (feed 1410)

..thats prob enough to give an idea for comparison. In a 1 gal pot, its quite light/dry by day two.

I do not foliar with anything in flower..

I'll look into the oystershell powder, great tip! I also checked the graph above, P is likely def locked out..and why I'm seeing the effects on the plant now.

I should have good reserves of N still, and my Cal Mag has a bit of N as well. I'd be looking for N if I was still in veg.

vahpor said:

My ppm readings, using the cheapo TDS-3 meter. I'm not sure what scale it functions on.

Click to expand...

It's the 500 scale. I.e., convert HM's PPM to EC by multiplying by 2, then dividing by 500. (I don't think TDS and EC are directly equivalent. But, that's how HM says to do it.). See:


You can calibrate using 1 gram of table salt in 1 liter of water which creates 1000ppm.

Those PPM readings you posted sound too high to me.

Dr. Who said:

Yeah just gotta love some of the crazy answers around here!
It's not over ferted!
Blackforest is close !!!!

It does start with what you amended with for pH stability...You need some more. Use Oystershell (powdered) for the added amounts...Add more Myco's at the soil build too!

Now then. By your pH measurements. I say your problem is Ca, Mg and P blocking by overall too low a pH swing at watering..

For the rest of this run (till you fix the buffers in the next) water with water/nute mix that is no lower then 7.0! Higher to 7.5 will be good.
You see, soil pH swings down by like a whole point when you water and as the soil dries back out it swings BACK up to the soils pH value it runs at.....under 6.5 those nutrients - Ca, Mg and P have a limited uptake to NO uptake (lockout condition)....Your getting that by the pH of your waterings being too low, The buffer being too light and the microbes working as hard as they can but not supported enough by the other facts....more can help some but, not enough....

Try what I say for the rest of this run and see I'm RIGHT!
Then adjust your soil for the NEXT run like I suggested...

Grow happy

Doc

Click to expand...

Man, you are one of the few people who actually come off as an authority figure here. I could probably use your help too!

The soil the grower is using already has fert in it. You don't need to add more fert. The better course of action would be transplant into a bigger pot with more of that soil. but it will be interesting to see how this works out. Those ppm levels you mention are way too high and too often. Giving that much every four days is going to kill you plant.

3 more things.
Your in soil - ppm's are meaningless! Simply feed as directed by the feeding chart of the nutrient maker for the week of growth indicated...

Polack has a point and I would say stop except for the fact that the plant has been in the soil over 5 weeks. The nutrient in the soil is used up. Keep feeding and once every 4 days is not bad - as long as there is a plain water watering between feeds......I might in your shoe's try feeding alternating like synthetic users. Feed, water, feed, water - just like FF says to.

Only worry about the pH of all in-going liquids - Forget about run off! Run off is not the pH of anything but the run off....Comparing the 2 to figure soil pH is very inaccurate.

Check this page out and scroll down to the "MOONSHINE MIX" for soil growers - water ONLY easy to build and it works. Great place to start for learning to make a water only soil.
I do my own Veg and Bloom soils and change at final up pot like Dankness.....
http://raredankness.com/FAQ.htm

Doc

Dr. Who said:

Feed, water, feed, water - just like FF says to.

Only worry about the pH of all in-going liquids - Forget about run off! Run off is not the pH of anything but the run off....Comparing the 2 to figure soil pH is very inaccurate.

Doc

Click to expand...

I use a liquid color code ph test kit. These kits don't malfunction. Since the mix stays the same it only takes a drop to ensure the final results are correct. I find one of these ph liquid test kits seem to last forever.

All good standard Doc advice...
But before a person pours a synthetic mix onto the medium smell it first. I find that if the mix has a rubber boot like odour(maybe not true with all fertilizer) it might be to strong for mj. Sometimes, because it's a weed the recommended dosage may have to be cut back a bit.

When pouring regular doses of fertilizers try to pour around what you think is the outer part of the rootbase, judging by the size of the plant. Avoid pouring nutrient enriched water that is mixed according to the instructions directly onto the base of the plant.

In the early days I,ve stunted and burn many a plant by following the intructions on the fertilizer label and not applying the fertilizer properly.

So yes, a plantpot with soil can only be fertilized on a schedule and in between feedings straight (ph 6.5) unadulterated water. The schedule for potted plants is usually on the label of whatever fertilizer the grower chooses to use.

I find that if I shake the water in a jug before I water it helps with the airation process.

Do these ferts that get added have any kind of recommendation on how to use them with certain soils? They don't seem to. It's not like they say, "if you are using this particular soil, then use the much of this product." I still say too much fert has been added and for no reason other than because the grower could, apparently not knowing the difference or how to handle the fert and the soil they purchased. I don't know if the fert in the soil is used up or not, but I know that a lot of people have come to the internet looking for help and the have done the exact same thing as this, adding fert to this soils happy frog and ocean forest. the bags don't say, "don't add any more fert for x-many weeks," so it's hard to know exactly what to do, but people don't seem to realize that many indoor plants don't need so much food because indoor lighting is very weak compared to the sun.

polishpollack said:

I don't know if the fert in the soil is used up or not, but I know that a lot of people have come to the internet looking for help and the have done the exact same thing as this,

Click to expand...

I think you make a great point. Often people say "don't feed anything for 3 weeks." In my case (mostly soilless, a dash of soil) I can feed half my normal strength in the first week, and full strength the 2nd week. So, it definitely depends on what the soil contains.

That's why I reach for runoff ppms for dialing in the unknowns like that. If it doesn't build up (to 2000-2200ppm), it's not overfed. At least that's what I've seen. Some nutes (synthetic) seem to burn leaves more than build up. Other nutes (with organics, kelp, blood meal, etc.) seem to build up without burning leaves. So, I see runoff ppms as a similar tool as watching leaf tips.

I'm pretty sure if the OP measured his runoff ppms the question of whether he's over or under fed would be answered. (It would have been better if he measured it each feeding and knew the trend.).

measuring ppms doesn't prevent the op from the freedom of adding more fert when it's not necessary. synthetic ferts are more easily absorbed; this is why they tend to cause faster leaf tip burning appearance. this really isn't a burn of course, it's just quick death of the leaf tip with a brown appearance and people have latched onto the use of the word "burn."

bird mcbride said:

I use a liquid color code ph test kit. These kits don't malfunction. Since the mix stays the same it only takes a drop to ensure the final results are correct. I find one of these ph liquid test kits seem to last forever.

All good standard Doc advice...
But before a person pours a synthetic mix onto the medium smell it first. I find that if the mix has a rubber boot like odour(maybe not true with all fertilizer) it might be to strong for mj. Sometimes, because it's a weed the recommended dosage may have to be cut back a bit.

When pouring regular doses of fertilizers try to pour around what you think is the outer part of the rootbase, judging by the size of the plant. Avoid pouring nutrient enriched water that is mixed according to the instructions directly onto the base of the plant.

In the early days I,ve stunted and burn many a plant by following the intructions on the fertilizer label and not applying the fertilizer properly.

So yes, a plantpot with soil can only be fertilized on a schedule and in between feedings straight (ph 6.5) unadulterated water. The schedule for potted plants is usually on the label of whatever fertilizer the grower chooses to use.

I find that if I shake the water in a jug before I water it helps with the airation process.

Click to expand...

Unless you are using insanely costly and highly accurate MEDICAL test strips - pH readings by liquid or paper are not very accurate.
The color of your run off or the color of your feed mix will effect your readings with liquids. When you are working with a pH zone of 1/2 a point or less.....USE a meter!

Dr. Who said:

Unless you are using insanely costly and highly accurate MEDICAL test strips - pH readings by liquid or paper are not very accurate.
The color of your run off or the color of your feed mix will effect your readings with liquids. When you are working with a pH zone of 1/2 a point or less.....USE a meter!

Click to expand...

And fertilizer companies like miracle grow don't help by adding color/dye to their fertilizer