Yellow Tops Every Grow

[Stoney Bear94]

Hey all,

I have pretty much the same issue every grow. Plants start out looking great, all green and beautiful. Once the stretch starts and during the transition to bloom, a bunch of the tops look weak, flimsy, and kind of yellow/lime. I even got rid of all my soil and started over with fresh soil. I'm watering with RO water, which comes out at about a PH of 6. When I test the runoff, it comes out around 6.7-7 (so I'd assume the soil is even a bit higher than 7). Not sure how this is possible if I'm consistently watering at 6. Maybe it's the amendments I'm using raise the PH? I use lots of earth worm castings, compost, and other organic stuff.

When I see this, what I do, is spray like once a day with water that has a tiny bit of manganese and iron in it, and I water with a bit of it too. That seems to help straighten them out. I'm assuming that because the PH of my soil is always high that the plants aren't uptaking enough of the micros and start to show the symptoms? Maybe they just need more of the micros when they start to transition and that's why I see it at that point every grow? People always say that you don't need to worry about PH when organic because it should balance itself out, but that's never seemed to hold true for me. Thanks dawgs.

 

[green_machine_two9er]

Sounds like you need to quit the ro and go with tap water. Ro typcally and no go with soil.
If you must ro then add a calmg and hopefully small amount of iron back to the water

 

[Marq1340]

Let me get a round or two off before the pros get settled

Is your tap that bad that you have to use RO water?

Specifically what soil are you using and why are you watering it till run off with organic fertilizer?

 

[HydoDan]

Let me get a round or two off before the pros get settled

Is your tap that bad that you have to use RO water?

Specifically what soil are you using and why are you watering it till run off with organic fertilizer?

You forgot to ask for a pic!

 

[Marq1340]

You forgot to ask for a pic!

And it was the first thing I noticed OP didn't share....

Discipline.

 

[Stoney Bear94]

I’m using roots organic soil, I don’t normally water til run off but when I suspected the PH was off I did so, in order to test it. I’ve been using RO so I don’t have to wait for the Chloramine to evaporate out, and I thought it was supposed to be better. But fair enough I’ll provide some pics

 

[MAK1]

I’m using roots organic soil, I don’t normally water til run off but when I suspected the PH was off I did so, in order to test it. I’ve been using RO so I don’t have to wait for the Chloramine to evaporate out, and I thought it was supposed to be better. But fair enough I’ll provide some pics

Although urea is not normally used in cannabis growing you have the same issue at the same early point in the grow.
Get ahead of the ball here and add nitrogen or urea right around the 12/12 switch. A little bit might help get past your high demand period during stretch. OR wait until you see an issue after stretch and add some N at that time. Organic grows tend to get low on N and P. It could be the roots haven't been correctly promoted. Did you water to develop better root system? Do you have solid roots?
Urea adsorbs well onto soil media. Once you get urea it into the soil it tends to stays there where as other nitrogen forms are salts that are soluble and get washed away with your other nutrients. Urea needs time (Miracle Grow feeds veggies every 2 weeks with urea) to be processed and assimilated and is not recommended at all for weed. I think you are so early and this urea all get consumed well before harvest. I don't find urea used in cannabis. I use urea but, I just don't tell people when or how.

 

[Nieto]

I used to have this exact kind of problems, and also tried pH'ing water and adding this and that micro, and usually everything just went from bad to worse.

For me the answer was not skimping on nutes once the plants get bigger and especially at/during switching them over to 12/12. I used to have this "less is better"-mentality with nutes, and I would always be afraid of overdoing them. When growing in soil I also don't believr in pH'ing your water, we grow all kinds of crops (chilies, tomatoes etc) succesfully with just plain water and the soil buffers the pH; why would cannabis be the one plant that would need pH adjustments? If anything I would say it just adds salts that build up in the dirt.

But something as simple as at least keeping the nitrogen-rich nutes on the same level as during 18/6 when switching over to 12/12, or even bumping N up just a little bit at that point has resulted in plants staying nice and green throughout.

 

[Kushash]

Hey all,

I have pretty much the same issue every grow. Plants start out looking great, all green and beautiful. Once the stretch starts and during the transition to bloom, a bunch of the tops look weak, flimsy, and kind of yellow/lime. I even got rid of all my soil and started over with fresh soil. I'm watering with RO water, which comes out at about a PH of 6. When I test the runoff, it comes out around 6.7-7 (so I'd assume the soil is even a bit higher than 7). Not sure how this is possible if I'm consistently watering at 6. Maybe it's the amendments I'm using raise the PH? I use lots of earth worm castings, compost, and other organic stuff.

When I see this, what I do, is spray like once a day with water that has a tiny bit of manganese and iron in it, and I water with a bit of it too. That seems to help straighten them out. I'm assuming that because the PH of my soil is always high that the plants aren't uptaking enough of the micros and start to show the symptoms? Maybe they just need more of the micros when they start to transition and that's why I see it at that point every grow? People always say that you don't need to worry about PH when organic because it should balance itself out, but that's never seemed to hold true for me. Thanks dawgs.

When the plants begin to flower. What do you do differently? What changes do you make at that point?
Do you proceed doing the same thing? Do you add bloom food? If yes, what food in what amounts?

 

[Stoney Bear94]

I do

When the plants begin to flower. What do you do differently? What changes do you make at that point?
Do you proceed doing the same thing? Do you add bloom food? If yes, what food in what amounts?

i didn’t mention this earlier, but I do feed some roots organic 2-.1-2 liquid ferts every few waterings.
My regimen is water, compost tea, water, liquid nutes.
I add compost, earth worm castings, bloom booster, azomite to the top soil throughout the grow.

 

[Stoney Bear94]

So actually my R

I used to have this exact kind of problems, and also tried pH'ing water and adding this and that micro, and usually everything just went from bad to worse.

For me the answer was not skimping on nutes once the plants get bigger and especially at/during switching them over to 12/12. I used to have this "less is better"-mentality with nutes, and I would always be afraid of overdoing them. When growing in soil I also don't believr in pH'ing your water, we grow all kinds of crops (chilies, tomatoes etc) succesfully with just plain water and the soil buffers the pH; why would cannabis be the one plant that would need pH adjustments? If anything I would say it just adds salts that build up in the dirt.

But something as simple as at least keeping the nitrogen-rich nutes on the same level as during 18/6 when switching over to 12/12, or even bumping N up just a little bit at that point has resulted in plants staying nice and green throughout.

So actually my R.O. Water comes out at a PH of 6, so I haven’t had to add any PH down or anything to get it there. It just seems strange that if I constantly put water in at a PH of 6 it comes out so much higher as runoff.

 

[Kushash]

I do

i didn’t mention this earlier, but I do feed some roots organic 2-.1-2 liquid ferts every few waterings.
My regimen is water, compost tea, water, liquid nutes.
I add compost, earth worm castings, bloom booster, azomite to the top soil throughout the grow.

OK, so a couple more questions about the bloom booster.
What is the name of the bloom booster and the NPK?
Everything else is probably fine.
What amounts of the bloom booster during the grow? Did you increase the bloom booster at the beginning of flowering? To what amounts?

 

[Hiphophippo]

Sounds to me like you’re washing away all your nutrients. And messing with pH and a soil that doesn’t need its pH message Wess which isn’t truly allowing your Micos to work to their full potential . Sometimes doing more is worse than doing less and I think in this case that’s it . I use r/o water Also but Add in calcium and magnesium and use Epsom salts. Can we see some pictures what size pots are you using

 

[Stoney Bear94]

I’m using a 30 gallon bed that I put 4 plants in with cover crops. I don’t typically water til runoff that was just a little bit for me to do my PH test. Here are some photos! The bloom booster is Dr. Earth flower girl. Just put some on a week or 2 ago. But the discoloration is just the tops which make me think it’s an immobile nutrient, where manganese and iron kinda fit the bill as far as yellowing on the inside out of the leaves. The only reason I can think is because those arE absorbed towards the lower end of the PH spectrum and I’m too high.

 

[myke]

Copied this
"To differentiate early signs of iron deficiency ask yourself which part of the leaf turns yellow first. As iron deficiency starts at the base, and slowly moves towards the tips. "

 

[Stoney Bear94]

Copied this
"To differentiate early signs of iron deficiency ask yourself which part of the leaf turns yellow first. As iron deficiency starts at the base, and slowly moves towards the tips. "

Ya I’m pretty sure it starts at the base and mores towards the tips. Just new growth. But I wonder is root cause high PH/bad absorption?

 

[myke]

Have you tried mineral water instead of RO?

 

[Marq1340]

I’m using a 30 gallon bed that I put 4 plants in with cover crops. I don’t typically water til runoff that was just a little bit for me to do my PH test. Here are some photos! The bloom booster is Dr. Earth flower girl. Just put some on a week or 2 ago. But the discoloration is just the tops which make me think it’s an immobile nutrient, where manganese and iron kinda fit the bill as far as yellowing on the inside out of the leaves. The only reason I can think is because those arE absorbed towards the lower end of the PH spectrum and I’m too high.

The lighter leaves are also tacoing from the side.
What are your tent conditions and light hight?

 

[MAK1]

I used to have this exact kind of problems, and also tried pH'ing water and adding this and that micro, and usually everything just went from bad to worse.

For me the answer was not skimping on nutes once the plants get bigger and especially at/during switching them over to 12/12. I used to have this "less is better"-mentality with nutes, and I would always be afraid of overdoing them. When growing in soil I also don't believr in pH'ing your water, we grow all kinds of crops (chilies, tomatoes etc) succesfully with just plain water and the soil buffers the pH; why would cannabis be the one plant that would need pH adjustments? If anything I would say it just adds salts that build up in the dirt.

But something as simple as at least keeping the nitrogen-rich nutes on the same level as during 18/6 when switching over to 12/12, or even bumping N up just a little bit at that point has resulted in plants staying nice and green throughout.

"why would cannabis be the one plant that would need pH adjustments?"
Cannabis is no different than those tomatoes. What is different is the nitrogen you are feeding them. You feed cannabis nitrates twice a week and you feed tomatoes urea and ammonium once in 2 weeks. Urea takes time to be broken down. A little nitrate today, a little tomorrow, some more after that for 2 weeks until that urea is nitrate so the plants can get to it. With cannabis we generally use ammonium only at the beginning or in veg. and then only nitrates after that. Nitrates raise the pH of soil water runoff.
Garden variety fertilizers use urea, these do not to raise the pH like nitrates. Urea is "sticky" and adsorbs onto organic matter so it does not get washed away like nitrate salt. Farmers don't fertilizes crops twice a week like we do, if they only used nitrates they would never sleep. Using nitrates makes it easier to hit the gas and stops faster as well.
Check out the nitrogen cycle, the phosphate cycle. After that its just a few minerals.

 

[Stoney Bear94]

75 degrees, 45% RH, lights about 18-20inches. It’s just the weak lime green leaves that have a lil taco to them. the healthier looking ones have no tacoing at all