Top Down Yellowing Leaves... After deep reflection I still can't figure it out...

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ethcan

ethcan

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I was doing one 900ml per plant feeding per day.

I can Set up a 3 drip feed tomorrow and see what my feed sizes end up being to achieve 20% runoff per feed.


i have also heard 20% per day runoff is ideal. as opposed To 20% each feeding.
 
Aqua Man

Aqua Man

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I was doing one 900ml per plant feeding per day.

I can Set up a 3 drip feed tomorrow and see what my feed sizes end up being to achieve 20% runoff per feed.


i have also heard 20% per day runoff is ideal. as opposed To 20% each feeding.
I would do atleast 10% per fert but again take my advice with a grain of salt. I would think probably 250-300ml 4 times. But that's a guess
 
ethcan

ethcan

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I would do atleast 10% per fert but again take my advice with a grain of salt. I would think probably 250-300ml 4 times. But that's a guess
I’ll give it a shot. Still wish some coco pros would hop in and give some input! But thanks Aqua Man.
 
needshelpguy

needshelpguy

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No. I mean hand watered when dry is how everyone was doing coco 5 years ago. With that popular oregon made organic nute line.

And all the guides i read when i was thinking to try it back then also showed to water when dry just like peat. Just dries a lot faster and holds calcium locked in the medium was the only caution.

The interenet is mostly good for fads. But as they change they get hidden back pages in search engines.

Tons of methods work for every medium. Plenty of proof all over of all kinds of methods.
Yeah I've stopped watering to run off full stop after some advice from a mate said hes done both and doesnt notice a difference with no run off I trusted his advice and plants seem fine, i checked run off about 3 weeks after and there was no salt build up, the run off just gave me to many humidity problems
 
needshelpguy

needshelpguy

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I was doing one 900ml per plant feeding per day.

I can Set up a 3 drip feed tomorrow and see what my feed sizes end up being to achieve 20% runoff per feed.


i have also heard 20% per day runoff is ideal. as opposed To 20% each feeding.
Yeah I agree you should only need to flush it out once daily not every watering
 
ethcan

ethcan

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Updates.

i flushed my plants hard.

Runoff now:
IN - pH 5.8 EC 1.2mS
OUT - pH 6.0 EC 1.4mS

Now, runoff still isn’t perfect but with no more heavy dry downs and regular feeding I expect that to slowly bring itself back in range. Will flush again next week.

For now, providing 500ml per plant per feeding now. Achieving 100ml of runoff per feeding. (20%)
First feed two hours after lights on, second feeding of the day 6 hours later. (18/6 photoperiod)

Immediately after the flush they looked immensely better and for the first time in weeks, I am seeing a turnaround.

Plants reaching for light... newest growth green and healthy, no longer purple dots on the petioles.
I think they were very locked out.

Enjoy the photos! Still not perfect, but fingers crossed, on the mend i think!

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C11EDB51 5E85 46A6 8063 D687F2976B6C

C17DD414 9A1F 4B80 9356 DAED6B96C244

F3B27AD7 7037 4145 8F8C B9BE5529E43E

6139635B BB61 43C1 BACF A5219C52035F

6139635B BB61 43C1 BACF A5219C52035F

F0E56A10 CE4D 4187 870B 7F2CDEF52E9B

104F0D10 B359 4131 83CB D282C241036D
 
cemchris

cemchris

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let me read through this. I was drinking my self into oblivion yesterday with the 4th
 
cemchris

cemchris

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Looks like you found your problem. When you get high runoff in coco you arent irrigating enough. As it drys out the medium PPM will shoot up.

I think you are gravy with the 2 for now as they start to flower I would prob up it to 3 and maybe even 4 depending on how big they get. Just pay attention to the runoff and up the frequency. As you up the frequency you can also lower the feed time just slightly. 3 waterings Ill run 17 sec. 2 waterings ill run 21 secs.

I hand water veg in 1 gal fabrics once a day. When they go into flower they are getting irrigated twice a day the first week. 3 times the 2nd week and after that they get moved to 3-4 times depending on the plant and size of them sometimes even 5. 3 waterings will show with yellowing on the bigger ones as the dry back with lights off is just a little too much. As will play with the final watering time anywhere from 2.5-1 hr before the lights go off. You want about 20-30% saturation when the lights come on (that is all gonna depend on humid/temp/enviro).
 
ethcan

ethcan

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Looks like you found your problem. When you get high runoff in coco you arent irrigating enough. As it drys out the medium PPM will shoot up.

I think you are gravy with the 2 for now as they start to flower I would prob up it to 3 and maybe even 4 depending on how big they get. Just pay attention to the runoff and up the frequency. As you up the frequency you can also lower the feed time just slightly. 3 waterings Ill run 17 sec. 2 waterings ill run 21 secs.

I hand water veg in 1 gal fabrics once a day. When they go into flower they are getting irrigated twice a day the first week. 3 times the 2nd week and after that they get moved to 3-4 times depending on the plant and size of them sometimes even 5. 3 waterings will show with yellowing on the bigger ones as the dry back with lights off is just a little too much. As will play with the final watering time anywhere from 2.5-1 hr before the lights go off. You want about 20-30% saturation when the lights come on (that is all gonna depend on humid/temp/enviro).


A few clarification questions for you...

Is my goal to basically to control runoff at all times? I'm assuming that keeping the EC stable within the media is a large priority now.

In what case would I look to add more EC as opposed to adding another feeding?

At what point would adding another feeding NOT be appropriate, in the case that it is just too much water? I assume there is a point at which you are hurting plant health due to excessive moisture. I'm aware coco holds plenty of oxygen at saturation which is why this is a bit of a conflicting thought for me, if you could help me understand better.

And about the 20%-30%. To be clear you are saying that the coco should have lost 70%-80% of it's moisture content during the dryback during lights off. Is this correct?
 
weedtech

weedtech

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Coco drains well - so Oxygen is not a problem. It is important to have enough moisture to prime the pump at lights on to have good flow during the day.

When I looked at the photos - I get more a sense of perhaps too much cal-mag? That looks like nutrient lock as others have noted. I get better results in my garden by taking the recommendations and cutting them in half and I tend to use much less CalMag than when I was doing mostly indicas. These days around 1 to maybe two milliters to a gallon.
 
ethcan

ethcan

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Coco drains well - so Oxygen is not a problem. It is important to have enough moisture to prime the pump at lights on to have good flow during the day.

When I looked at the photos - I get more a sense of perhaps too much cal-mag? That looks like nutrient lock as others have noted. I get better results in my garden by taking the recommendations and cutting them in half and I tend to use much less CalMag than when I was doing mostly indicas. These days around 1 to maybe two milliters to a gallon.
Yes. I established quite early they were heavily locked out. It appears to be on the mend after a heavy heavy flush.
 
cemchris

cemchris

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A few clarification questions for you...

Is my goal to basically to control runoff at all times? I'm assuming that keeping the EC stable within the media is a large priority now.

In what case would I look to add more EC as opposed to adding another feeding?

At what point would adding another feeding NOT be appropriate, in the case that it is just too much water? I assume there is a point at which you are hurting plant health due to excessive moisture. I'm aware coco holds plenty of oxygen at saturation which is why this is a bit of a conflicting thought for me, if you could help me understand better.

And about the 20%-30%. To be clear you are saying that the coco should have lost 70%-80% of it's moisture content during the dryback during lights off. Is this correct?

Runoff EC is a good way to judge but that comes with a grain of salt. Your medium PH and EC will be different then whats coming out of the pot. It can still be a good tool to keep track of whats going on with buildup and what not.

Adding EC can be a double edged sword. As long as they arent showing signs they are hungry let it rock. I generally don't try and go above 900 ppm in DTW on anything (strain dependent)

You will know when you have too many feeds. You will get the typical end leaf bend. Ive gone as high as every hour in flower with lots of runoff (like 30-40% total). You never want it "dry" per say. If the top of the coco is turning light brown and dry on the majority of the top of the pot you prob aren't irrigating enough.

Yes correct.
 
ethcan

ethcan

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63
Runoff EC is a good way to judge but that comes with a grain of salt. Your medium PH and EC will be different then whats coming out of the pot. It can still be a good tool to keep track of whats going on with buildup and what not.

Adding EC can be a double edged sword. As long as they arent showing signs they are hungry let it rock. I generally don't try and go above 900 ppm in DTW on anything (strain dependent)

You will know when you have too many feeds. You will get the typical end leaf bend. Ive gone as high as every hour in flower with lots of runoff (like 30-40% total). You never want it "dry" per say. If the top of the coco is turning light brown and dry on the majority of the top of the pot you prob aren't irrigating enough.

Yes correct.
Could you please provide me with a visual of the signs of too much water? The "end leaf bend"

I feel like this is something I feel I've gotten very wrong in the past.
 
Aqua Man

Aqua Man

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Could you please provide me with a visual of the signs of too much water? The "end leaf bend"

I feel like this is something I feel I've gotten very wrong in the past.
I think he meant to much nutrients (ppm) not to much water. You can't really give to many irrigations imo (it's just a bit more wasteful if not needed) Atleast that's what I think he is saying.

I think he is referring to clawing from to high of ppm. Looks like this.

If I'm interpreting wrong I'm sure he will correct me.
 
Cannabis leaves tips down sm
ethcan

ethcan

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63
Updates. Still having issues.

did some extremely heavy flushing and got my EC in check.

began irrigating twice daily in an 18 hour photoperiod, getting 20% run off each time.

Some plants progressing and looking worse as opposed to better.


input: pH 5.9 EC 1.18mS.
runoff: pH 6.5 EC 1.65mS


runoff has risen dramatically in the run of in two days.

do I need to lower my feed EC, or increase my feedings? As is they are staying pretty wet pretty much all the time now.

B63DA776 B6E8 4A2E A796 CCD28BED1003
 
Aqua Man

Aqua Man

26,480
638
Updates. Still having issues.

did some extremely heavy flushing and got my EC in check.

began irrigating twice daily in an 18 hour photoperiod, getting 20% run off each time.

Some plants progressing and looking worse as opposed to better.


input: pH 5.9 EC 1.18mS.
runoff: pH 6.5 EC 1.65mS


runoff has risen dramatically in the run of in two days.

do I need to lower my feed EC, or increase my feedings? As is they are staying pretty wet pretty much all the time now.

View attachment 997226
Just my opinion. If runoff is rising you need to feed more often. Lowing the light intensity a little until you get it sorted would also be a recommendation.
 
ethcan

ethcan

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63
Just my opinion. If runoff is rising you need to feed more often. Lowing the light intensity a little until you get it sorted would also be a recommendation.
Will do both of those things.

what will happen to the plants with less established root systems? I’m sure the healthy ones will make it now problem with more feedings but I’m worried the slower ones will drown.
 
Aqua Man

Aqua Man

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Will do both of those things.

what will happen to the plants with less established root systems? I’m sure the healthy ones will make it now problem with more feedings but I’m worried the slower ones will drown.
You can't drown a plant unless the water is stagnant and depleted of oxygen. It doesn't actually drown it just doesn't have enough oxygen.

Look at hydro much the same roots are submerged all the time.
 
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