need help with a leave-syndrom thats growing rapidly

  • Thread starter mannitu68
  • Start date
  • Tagged users None
M

mannitu68

52
18
hello folks,
forgive me when not introducing myself, i will manage to do so later :). I just opened my tent and was surprised to see that even more leaves are affected now than yesterday. I bet you get a lot of posts from people that sound exactly like this, but i really have no other solution what to do. Ive used all information and websites to my best knowledge and abilities, but i havent been able to make sure what deficiency or other symptom is going on here. This is my 1st grow, i had 2 problems so far that i have been able to solve on my own, one was a phosphorus deficiency in mid veg, i tended to be a little to shy with fertilizers, second was a problem with chronic underwatering, i was too afraid to drown my plants, in the end one plant developed twisted and deformed leaves and some brown spots, mabye boron deficiency i thought. However ive been able to get rid of both things fast and succesfully, now after 3 weeks in flower trouble strikes again, hard and fast. I saw it on 1 or 2 leaves, didnt think much about it, now its 3 days later and i see about 10 leaves affected. I will try to give as much information as i can, i appriciate if you dont give any random ideas or what it could be, but only tell if it def. rings a bell and you know whats going on here. Im tired out after reading and watching videos, many with contradicting analazys and resumes.

I should say that i have 2 pots, 1 plant is in a 3 gallon pot, thats the one that is affected. 2 other plants are sharing a 4, gallon pot, they show no signs of problems, all are using same soil, watering, fertilzers concentration. The affected plant is a little smaller than the ones in the big pots, so it takes water and nutrients in slower than the big pot. i weigh the pots each day and it loses only about half the weight than the big pot with the 2 plants.


Time: 3 weeks into flowering 12/12

Symptom: leaves develope small, brown-rusty spots, together with some tiny green-yellowish discolouring, it starts from the inside of the leave, not the tips. Spots become necrotic and after a few days some leaves are totally dead and dried out and you could easily break them off. Upper leaves are affected, but not the small ones on the very top around the buds. Lots of leaves are showing first brown spots now.

medium: soil with 6,4ph, im watering with tapwater, a 2 component fertilizer and a small amount of calmag, always around ph 6, sometimes a little less or more.

Light, temp and enviroment: 20-24 degree celsius, im keeping the humidity under 60% now, most around 45-55%. Light is plenty, 150 watt LED panel for 2x2 feet.


Fertilizer: for the most time i used a simple 7-5-6 allround fertilizer from the supermarket and have to say i was pretty happy. Besides a small phosphorus def. in early stages..i doubled up the concentration t 4ml/l and everything run perfect. Then 3 weeks ago, i deceided to buy another fertilizers, because i read its a good idea to reduce Nitrogen. So i got myself a 2 component-mineral fertilzer with the NPK ratio 8-0-0 in bottle A and 0-4,2-16 in bottle B. Its also supposed to have all the other micronutrients for cannabis, at least it says so. Youre supposed to mix them up. Right now im using, per liter : 2ml of A, 4ml of B and 1ml of calmag (4%calcium/1%magnesium)

i tend to make a "light flush" about every 4 weeks, before watering i put about 1,5l tapwater, ph to 6,0, in the pots, then i water regular until it loses about the same amount of water at the bottom, just to flush out any possible amounts of dried salts at the bottom. Ive never been aggressiv with fertilizers, even now im just using 75% of recommendet dosage. I did check the runoff water one time, but ph was unspectacular, just over 6.0.

because of the nature of flowering, i did first suspect that this must be a phosphorus or potassium deficiency, because of elevated requirements in flower. I did however already have phosphorus def, at least im sure of that, allthough the spots look a little familiar, it started from the bottom. And for potassium def, from the pics ive seen it looks different, starting at the leave tips, first with yellowing. This time, the bottom fan leaves are unaffected. It also cant be anything light/heat stress related, the plants in the bigger pot are a little bit taller, nearer to the LED and show no sign of trouble. I really would appriciate some advice, sure its a common thing, im probably not doing things differently than other people.

what "riddles" me is that in the big pot, one of the 2 plants grew very good, its about twice the biomass and also the buds are larger, it sure has larger needs on nutrients, but it doesnt show any sign of deficiency. Could this be a hint that this has something to do with toxicity/nutrtient lockout etc? Just some ideas, i really have no idea.

i feel like this will affect the whole plant in a few days if im not acting quickly :(
i did turn down the light from 150w to 100w, with the idea to slow growth and metabolism down until i find a solution..probably a naive idea, but i dont know what else to do right now.

yours, mannitu
 
DSCI2279
DSCI2278
DSCI2277
DSCI2275
DSCI2273
DSCI2259
Last edited:
Shaded_One

Shaded_One

632
143
Light, temp and enviroment: 20-24 degree celsius, im keeping the humidity under 60% now, most around 45-55%. Light is plenty, 150 watt LED panel for 2x2 feet.


Fertilizer: for the most time i used a simple 7-5-6 allround fertilizer from the supermarket and have to say i was pretty happy. Besides a small phosphorus def. in early stages..i doubled up the concentration t 4ml/l and everything run perfect. Then 3 weeks ago, i deceided to buy another fertilizers, because i read its a good idea to reduce Nitrogen. So i got myself a 2 component-mineral fertilzer with the NPK ratio 8-0-0 in bottle A and 0-4,2-16 in bottle B. Its also supposed to have all the other micronutrients for cannabis, at least it says so. Youre supposed to mix them up. Right now im using, per liter : 2ml of A, 4ml of B and 1ml of calmag (4%calcium/1%magnesium)

i tend to make a "light flush" about every 4 weeks, before watering i put about 1,5l tapwater, ph to 6,0, in the pots, then i water regular until it loses about the same amount of water at the bottom, just to flush out any possible amounts of dried salts at the bottom. Ive never been aggressiv with fertilizers, even now im just using 75% of recommendet dosage. I did check the runoff water one time, but ph was unspectacular, just over 6.0.

Alright so just a few things I want to highlight to possibly help you:

  • You want your temps to be closer to 28/30c day time and around 19-21c night time
  • 150 watts is not plenty to flower a 2x2, it's adequate but not ideal(250-300w would be more ideal)
  • Your fert schedule has been all over the place, and you said it yourself you were seeing a K deficiency early on in veg which would only get WORSE going into flower when the plant becomes the hungriest
  • Flushing in soil every 4 weeks, can I ask why? Seems to be unnecessary imo and I don't bother with it myself

My advice is to find yourself a nutrient line whether it be organic or synthetic that is well known and proven results with feed schedules already clearly defined that you can just follow. Get everything else VPD wise in check and you'll be okay. It's just you may not see the best results considering how far you are into flowering already.
 
Shaded_One

Shaded_One

632
143
what "riddles" me is that in the big pot, one of the 2 plants grew very good, its about twice the biomass and also the buds are larger, it sure has larger needs on nutrients, but it doesnt show any sign of deficiency. Could this be a hint that this has something to do with toxicity/nutrtient lockout etc? Just some ideas, i really have no idea.

Also this sentence is alarming and confusing. Are you planting multiple seeds into one pot? Do you have drainage trays? What are you using for containers/pots and do they have drainage holes? Can you take a picture of your entire grow space/plants and post it here please.

"2 other plants are sharing a 4, gallon pot"

I missed this. And this is a huge cause of concern and likely a big part of your problem. You've got plants sharing a container fighting for nutrients. You have kids? Siblings? You ever try to share a meal together? Who gets the most food? You see where I'm going with this.
 
M

mannitu68

52
18
-not trying to be rude, but nothing that you said makes sense to me. With 250-300watt (pretty absurd, never have heard that for a 0.36 squaremeter tent) i would be somewhere between 1400-2000 PPFD. im at 900 now. what you said would mean 800-900 watts per squaremeter, yeah good luck with that. Maybe if you want to grow and smoke your plants all in one step. Just stick thge exhaust-pipe in your mouth then and inhale.Or maybe youre simply living in the light-world of 10 years ago and have no clue what modern LED-panles are capeable of. Youll achieve 1000umol PPFD over the complete area with a 400watt lamp per squaremeter.

-I never said i have a K deficiency, i said i had a phosphorus deficiency, i said that twice, no idea how you come to K.

-about the 2 plants in i pot: yeah, might not be ideal, was an emergency solution and will be the last time, however this is not the pot with troubled plant.

about your temp recommendations: dozen of people give multiple temp recommendations. My temps are the way they are and until now the plants grew fine. Im not gonna buy different equipment or even a heater to furfill someones recommendation, when i clearly dont see any connection to the very urgent problem i have.


and about your fertilizer advice: I have the cannabis fertilizer i have now. The ingredients are printed on the package. I think it makes sense to learn how to recognize a problem/deficiency and to act accordingly and not to just buy another fertilzer and hope that the problems will vanish. I dont even know if the fertilizer is the problem and you also dont know, so what sense would it make to speculate. I might buy something else next time, right now ive got other concerns.
 
Last edited:
crimsonecho

crimsonecho

Self-Proclaimed Don Quixote
Supporter
2,515
263
Alright so just a few things I want to highlight to possibly help you:

  • You want your temps to be closer to 28/30c day time and around 19-21c night time
  • 150 watts is not plenty to flower a 2x2, it's adequate but not ideal(250-300w would be more ideal)
  • Your fert schedule has been all over the place, and you said it yourself you were seeing a K deficiency early on in veg which would only get WORSE going into flower when the plant becomes the hungriest
  • Flushing in soil every 4 weeks, can I ask why? Seems to be unnecessary imo and I don't bother with it myself

My advice is to find yourself a nutrient line whether it be organic or synthetic that is well known and proven results with feed schedules already clearly defined that you can just follow. Get everything else VPD wise in check and you'll be okay. It's just you may not see the best results considering how far you are into flowering already.
150w is plenty of light for a 2x2
 
PrimoClonesCanada

PrimoClonesCanada

Supporter
203
93
Really...so you'd recommend a 300w for a 4x4? Let's agree to disagree on that point.
Hey man not trying to argue but 2x2 is 4 square feet @ 150 w = 37.5 watts per square foot

4x4 is 16 square feet @ 300 w= 18.75 watts per square foot. so the comparison is not right at all

You don't think 37.5 per square foot is good?

I use 650 in a 5x5 and it works fine.

Rusty spots on your leaves is usually calcium deficiencies, plus you already had phosphorus deficiencies in veg would make me think it's phosphorus again as now it needs way more than when your in veg.
What medium are you growing in? Coco
I never flush but I'm use organic soil.
I know on coco it's normal to flush frequently.

Happy Growing
 
Last edited:
Dudethatsweet

Dudethatsweet

21
13
To me it looks like you have a K and maybe a Mg deficiency. Perhaps LED light burn. How far off the canopy is your light?
From the tight internode spacing in the pics, I'd say your light is fine to flower. You may have it a little too close.
IMHO, if you wait until your plants show signs of deficiency, you're too late. Stunted growth will result and plants won't reach their full potential.

LED lights do not need to be as close as people think. Some of the best that I have ever smoked (34+%) was grown under an SF-4000 and the plants were over 4.5 feet tall at finish.

Put the LED close to the canopy for insane leaf growth and tight internode spacing. Place it 3 to 4 feet away to get enough stretch to make room for buds to grow.

Good job so far, no need to "slow things down". Determine a more accurate feeding plan and take those girls to the finish line.

DtS
Green side up^
 
M

mannitu68

52
18
thanks for your efforts. I will upload a picture from the fertilizer i use. It was recommendet to me once, but people like to recommend, i just took the first thing to get my hands on. At that point i didnt really want to buy something new, because the allround-fertilizer has done an excellent job before. I just wanted to reduce nitrogen. Maybe the ingredients can answer some of your questions. It has lots of calcium and magnesium in it...per ml, even more than my calmag supplement. What did confuse me a little about this product is, it always recommends same amount of A and B. I was thinking its 2-component, so you can reduce the component with N over time...but on the package, they always recommend same amount of A and B...slightly increasing over time. in the 1st 6 weeks of flower, they recommend 2.5-4 ml of A and 2.5-4 ml of B. For late flower, they say 4-5ml A and 4-5 ml B. Not what i was expecting. However, im feeding 2ml A and 4ml B now. Also 1-1.5ml calmag per liter. But like i said, that fertilizer has whapping 16% calcium and 1,5% magnesium per ml. Calmag has 4%/1%

Now some compressed infos, it might go under in my previous long text:
-2 pots in the tent, 1 with 2 flowers in it, 1 with 1 flower. Yes i know, not good. However, problems occur in the single-plant pot. Its the smaller plant. Theres 1 plant in the community-pot, thats literally twice the size than the "sick" one. Its also taller and closer to the LEDs, but showing no signs of light or heatstress. LEDS are close, but its a large panel with low diode density, it isnt even capable delivering more than 900 PPFD. But it does so all over the surface. Also the small leaves at the very top are not affected, its the ones 1 step lower..generelly in the upper half of the plant

-im growing in a regular "bio-soil", its general multi purpose soil, small parts of perlite and humus in it. PH is 6.4 at opening.
- to the possible phosphorus deficiency: It read that phosphorus is mobile and older leaves will be affected. Thats exactly what happened in early/mid veg. But this time the lower half is unaffected if that wasnt the case, yes, the spots do look somewhat similar.


im really afraid this will spread all over.
 
DSCI2281
DSCI2282
DSCI2287
M

mannitu68

52
18
can it have something to do with overwatering? because the troubled plant has much more soil for itself allthough its smaller and drinking less..i water every 2 days and its pot always has more humidity left than the other one which is very dry. But the signs for overwatering would be droopy leaves, right?


this pic must be about 10-12 days old. Just wanted to show you the light. many stems and buds are even closer to the light now. But its fine. You cant really make out which plant is which, but the pot with the sick plant is in the front, when you open the door. The 2 ones at the back are happy.
 
DSCI2229
Last edited:
TSD

TSD

1,058
163
can it have something to do with overwatering? because the troubled plant has much more soil for itself allthough its smaller and drinking less..i water every 2 days and its pot always has more humidity left than the other one which is very dry. But the signs for overwatering would be droopy leaves, right?
Are you watering both pots at the same time and the same amount regardless of moisture level?
 
M

mannitu68

52
18
man i think i fck up....
well, i feed like this, i water them, slowly, until first drops come out of the bottom holes. In the last time, ive done this every 2 days, sometimes 3. The pot with the 2 plants was always very light, not only are they 2, theyre larger. Almost impossible to drown them, they drink so fast. The pot of the smaller one didnt lose that much weight. It still watered it until drops come out...just that it didnt take that much. So in this regard, i fed it less, because it took less to fill up the pot. Maybe 3 gallon is a lot for a plant thats not that huge and i should have let i dry out? I underwatered it in the veg so maybe this time its the opposite. It would make sense in one way, because i feed all plants the same nutrients, why should only one show signs of def. or toxicity? Oh dear.
 
TSD

TSD

1,058
163
man i think i fck up....
well, i feed like this, i water them, slowly, until first drops come out of the bottom holes. In the last time, ive done this every 2 days, sometimes 3. The pot with the 2 plants was always very light, not only are they 2, theyre larger. Almost impossible to drown them, they drink so fast. The pot of the smaller one didnt lose that much weight. It still watered it until drops come out...just that it didnt take that much. Maybe 3 gallon is a lot for a plant thats not that huge and i should have let i dry out? I underwatered it in the veg so maybe this time its the opposite. It would make sense in one way, because i feed all plants the same nutrients, why should only one show signs of def. or toxicity? Oh dear.
Yeah I'd say you're overwatering the single one. 2 plants in a 4 gal is going to have vastly different needs than 1 in a 3 gallon... that's the tricky part about having different size pots or different age plants, really gotta keep track of when you water. I'm not sure if that's your whole or only issue, but sounds like it's definitely an issue.
 
M

mannitu68

52
18
yeah something in my gut tells me thats it. I was afraid to let it dry out too much because of my previous experience...i was thinking now that the plant has roots through the whole pot, it can deal better with water, also its got holes in the bottom. Man sh+t right now its even wetter, because on wednesday evening i flushed it. this time im gonny wait until the pot dried out nicely and then note the weight. Hope i didnt do too much damage.
 
Shaded_One

Shaded_One

632
143
yeah and i’d recommend a 600w for a 8x8 and so on rofl

600w in an 8x8 is laughable....I have a 4x4, I can do math and divide that in half to get a 2x2 and compare wattages in equal ratios. I would not grow weed in a 4x4 with 300w of light unless it was one plant directly under the light but hey that's just me. I would say 400w is passable. 600w is ideal.

@mannitu68 your post was 8,975 words long with practically zero formatting. Good luck with your grow bud you seem to have it all figured out.
 
M

mannitu68

52
18
@TSD
have you ever encountered or seen this, that these symptoms show from overwatering? What would be going on then, absence of oxygen or maybe rootdamage already?

@Gandalf. nah i havent figuered everything out and also didnt want to be rude. just if somebody addresses me stupid, i answer accordingly. Also your answer just wasnt helpful. Nah your math is garbage. Funny is you shouldnt even need math for that...simply visualizing a 2x2 and a 4x4 and it still doesnt ring a bell for you, even hours later.Lol.
 
Last edited:
crimsonecho

crimsonecho

Self-Proclaimed Don Quixote
Supporter
2,515
263
600w in an 8x8 is laughable....I have a 4x4, I can do math and divide that in half to get a 2x2 and compare wattages in equal ratios. I would not grow weed in a 4x4 with 300w of light unless it was one plant directly under the light but hey that's just me. I would say 400w is passable. 600w is ideal.

@mannitu68 your post was 8,975 words long with practically zero formatting. Good luck with your grow bud you seem to have it all figured out.
bro take a math class
 

Similar threads

Top Bottom