Flowering Stage - Need Help with Diagnosis - Nute Burn or Potassium?

  • Thread starter ottomangrows
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ottomangrows

ottomangrows

3
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Hi All,

I'm a new grower working toward my first harvest of 5 plants. Two are looking ill in the flowering stage. (Other three look fine on same feeding schedule.)

I need a little help from experienced growers on:
  1. A diagnosis
  2. How to treat at this stage in the game (if potassium deficiency.)

I am thinking this is either Nute Burn or Potassium Deficiency.

I am going to lower the canna A B nutes to 2 ML per liter of water; .5 ML of Cal Mag per L of Water.

If this is Potassium, how do I adjust (or do I need to add a supplement)?

THANKS IN ADVANCE FOR YOUR GUIDANCE!

THESE ARE NORTHERN LIGHTS AUTOFLOWERS AT 9 WEEKS:
  • LIGHTS: 18 inches above plants
  • WATERING SCHEDULE: What daily with fertigation until run-off
  • WATER PH: 5.75 PH (Coco)
  • SOIL: Coco Coir
  • NUTES: Canna Coco A B (2.5 ML of each nute - per L of Water)
  • OTHER SUPS: Cal-Mag Plus at 1 ML per L of Water
  • TEMP: Steady 70
  • HUMIDITY: Steady 55
  • STATUS: 9 Weeks
  • TYPE: Northern Lights - AUTOFLOWER

Flowering stage   need help with diagnosis   nute burn or potassium
Flowering stage   need help with diagnosis   nute burn or potassium 2
 
mysticepipedon

mysticepipedon

4,738
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It's not nute burn and I don't think it's potassium, either. (There may be a touch of nute burn, but it's not your big problem.)

I can't say for sure. Is it possible that your pH fluctuates a lot?
 
ottomangrows

ottomangrows

3
1
It's not nute burn and I don't think it's potassium, either. (There may be a touch of nute burn, but it's not your big problem.)

I can't say for sure. Is it possible that your pH fluctuates a lot?
My PH is pretty steady.

I use an automatic fertigation system that waters 5.75 PH (Coco Coir) every morning for 90 seconds (about 20% run-off).

It is a 20 Gallon system that I only have to refill once a week.

I am very curious, because it is only affecting 2 of 5 plants and they are all on the same feed schedule/system.

The two plants affects are a Northern Light and a Blue Dream. I have another Northern Light and Blue Dream doing just fine on the system.
 
RookieBuds

RookieBuds

119
63
One of mine is doing that but not as bad, i believe my issue is calcium lockout and/or pH swing. I also do believe 5.75 is on the low side, maybe aim for closer to 6.1 and see if that helps?
 
mysticepipedon

mysticepipedon

4,738
263
40% of your plants is a lot. If almost half don't like how they're being treated, you have to adjust.

I don't use coco, but I believe @RookieBuds is correct, and that pH is a little low.
 
ottomangrows

ottomangrows

3
1
Thanks all. I do appreciate your replies/thoughts.

If anyone else has any other thoughts (beyond PH issue), please do share.
 
extractoilminussixty

extractoilminussixty

270
93
  • Little late here in reply, but I am learning as well. My last grow did the same thing I ended up getting a nice harvest with good quality material but the leaves just dried up basically …turns out my ph was low. I spent the money on a digital instant pH reader and it has been worth every penny!
  • Quote-“pH level out of range: Potassium has an optimal pH range between 6.1 and 7.1. If the pH of the soil or water/nutrient solution is above or below that, potassium won’t be available to the plant.”
  • Cont-
  • “Poor soil: Soil that isn’t suitable for cannabis, or is low-quality, will likely be deficient in potassium.
  • Giving too much calcium: Too much calcium can lock out potassium and magnesium.
  • Not providing adequate amounts of nutrients: Not all cannabis strains have the same nutrient requirements. A feeding regimen that works for one cannabis variety may not provide enough nutrients for another.”
Not certain if that’s your problem, but sure looks a lot like it.
I’m now using pH up and down as well as more potassium & phosphorus nuits
(I really have a hard time telling the difference between the two deficiencies)
  • 1625664647613


  • 1625664694278

1625664775651



Below is Phosphorus deficiency—
Plants that are deficient in Phosphorus will look abnormal [leaves will be abnormally shaped] with possible discoloration.

The-Macro-Nutrients.jpeg
 
extractoilminussixty

extractoilminussixty

270
93
You know, after going back and looking at your original posted northern lights pictures, I’d have to say that’s definitely phosphorus deficiency !
 
extractoilminussixty

extractoilminussixty

270
93
Bloomspect 300 Led
Bloomspect 600 Led
Viperspectra 300 Led
all draw about 130 w - 150w each

Nothing great, but have 7 so figured I’d run them through their life they seem to work fine for me
Much better led lights out there obviously
 
Mugwort

Mugwort

394
63
Could it be light burn? I couldn’t tell from the pic the condition of lower leaves. It looks like pistils that get the most exposure are white while there are some reddish ones within lower parts of bud. I just downloaded the light measuring app called “Photone”. Has anyone used this app? I wonder how accurate it is?
 
Og_punkgenetics

Og_punkgenetics

180
63
Hi All,

I'm a new grower working toward my first harvest of 5 plants. Two are looking ill in the flowering stage. (Other three look fine on same feeding schedule.)

I need a little help from experienced growers on:
  1. A diagnosis
  2. How to treat at this stage in the game (if potassium deficiency.)

I am thinking this is either Nute Burn or Potassium Deficiency.

I am going to lower the canna A B nutes to 2 ML per liter of water; .5 ML of Cal Mag per L of Water.

If this is Potassium, how do I adjust (or do I need to add a supplement)?

THANKS IN ADVANCE FOR YOUR GUIDANCE!

THESE ARE NORTHERN LIGHTS AUTOFLOWERS AT 9 WEEKS:
  • LIGHTS: 18 inches above plants
  • WATERING SCHEDULE: What daily with fertigation until run-off
  • WATER PH: 5.75 PH (Coco)
  • SOIL: Coco Coir
  • NUTES: Canna Coco A B (2.5 ML of each nute - per L of Water)
  • OTHER SUPS: Cal-Mag Plus at 1 ML per L of Water
  • TEMP: Steady 70
  • HUMIDITY: Steady 55
  • STATUS: 9 Weeks
  • TYPE: Northern Lights - AUTOFLOWER

View attachment 1126055View attachment 1126056
you want to test the ppms and ph of the run off next watering, it looks like it could be a lock out issue. Also if you have it sitting in a reservoir, you want to make sure the pH is what you think it is before it initiate the watering. Somethings can make wild PH swings happen due to The chemical composition and mineral content of the supply water. You might PH at 5.75 the day before and it raises overnight
 
dbrzz

dbrzz

166
43
My PH is pretty steady.

I use an automatic fertigation system that waters 5.75 PH (Coco Coir) every morning for 90 seconds (about 20% run-off).

It is a 20 Gallon system that I only have to refill once a week.

I am very curious, because it is only affecting 2 of 5 plants and they are all on the same feed schedule/system.

The two plants affects are a Northern Light and a Blue Dream. I have another Northern Light and Blue Dream doing just fine on the system.
Your PH for cococoir is best at 5.8-6.3 range. Also I have had better luck using epson salts than cal/mag preparations. I have encountered lockout because of high calcium levels in the coco. I make sure my nutrient mix has a good amount of calcium like 7%. Then supplement the mag with the epson salts. Works well for me!!
 
dbrzz

dbrzz

166
43
Could it be light burn? I couldn’t tell from the pic the condition of lower leaves. It looks like pistils that get the most exposure are white while there are some reddish ones within lower parts of bud. I just downloaded the light measuring app called “Photone”. Has anyone used this app? I wonder how accurate it is?
Photone is useless as a light meter. Its more of a toy than a calibrated scientific par measuring device. Light burn is really rarer than new growers realize. The heat from being too close to the light is usually what damages the leaves. Once the leaves surface temperature hits 85F, they cease to grow and go into self preservation from the excessively high leaf surface temperature. The plant can regulate its leaf temps by transpiration of water to cool the leaves. This is why fans for air movement is critical in the tent environment. Remember tent temperature is not leaf surface temperature.
 
Derelictus

Derelictus

19
3
Hi! I'm new too. Welcome to both of us. Buds are getting frosty bud!

I experienced this same issue because...well, I'm an idiot and think I'm smarter than I really am by skipping large portions of tiny text on my nutrient bottles. I was PH balancing my water before adding the nutes, which have buffering agents. Who knew!! My target was 5.8. Didn't catch this at first because starting out with small dosing and blah, blah, blah. But 1 morning I found 2 leaves looking just like yours. Anyway, you're obviously a lot smarter than I am and read all directions twice (including the tiny text), and I don't mind self-deprecating here, but your leaves look exactly like mine did before raising my PH to 6.0. They recovered fast once they were able.

My situation made perfect sense, but I don't think you can go wrong by bumping up your target a bit. 5.75 is a bit lean.

Good luck and nice work!
 
atmosphere

atmosphere

26
13
Photone is useless as a light meter. Its more of a toy than a calibrated scientific par measuring device. Light burn is really rarer than new growers realize. The heat from being too close to the light is usually what damages the leaves. Once the leaves surface temperature hits 85F, they cease to grow and go into self preservation from the excessively high leaf surface temperature. The plant can regulate its leaf temps by transpiration of water to cool the leaves. This is why fans for air movement is critical in the tent environment. Remember tent temperature is not leaf surface temperature.
Resistance to heat also has a lot to do with EC levels in the root zone . Even with run off, EC levels can build up to the point that it causes problems.
 

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