Some Problems (Yellowing, Browning...)

P

Pathaway

Member
Hi. I have 4 Kali Mist plants (LST) and 1 Afghan Kush in day 39 Flowering. There are some problems with them and I'll appreciate any help. Here are some pics:
First a general pic (it's just after watering so they are a little droopy):
P1000564.jpg

Now the problems:
P1000511.jpg P1000508.jpg P1000541.jpgP1000592.jpgP1000594.jpg
The yellowing of the tips first appeared around 20-th day of vegging. It affects mostly one of the plants, which is also affected by the browning. The yellowing appeared on another of the plants 1-2 weeks ago.

Now the browning:
P1000613.jpgP1000616.jpg
It's only on these three leafs. Do you know what is it? I hope it's not some kind of fungus.

Here is some info on the grow:

Air Circulation: Big fan :)
Light: 400W HPS
Temps: 64-75F
Humidity: 70-95% (I know it's extremely high. I started using dehumidifier and I hope to lower it to 60-70%)
Ferts: Bio-Grow, Bio-Bloom and Green Sensation
PH: around 7 I think (I use the color strips test)

The feeding (Days in flowering):
Day 3
Bio-Grow: 1lm/l (about 4ml/gallon)
Bio-Bloom: 1lm/l (about 4ml/gallon)

Day 7
Bio-Grow: 1lm/l (about 4ml/gallon)
Bio-Bloom: 1lm/l (about 4ml/gallon)

Day 11
Bio-Grow: 1lm/l (about 4ml/gallon)
Bio-Bloom: 1lm/l (about 4ml/gallon)

Day 14
Bio-Grow: 1lm/l (about 4ml/gallon)
Bio-Bloom: 2lm/l (about 8ml/gallon)

Day 20
Bio-Grow: 1lm/l (about 4ml/gallon)
Bio-Bloom: 2lm/l (about 8ml/gallon)

Day 25
Bio-Grow: 0.5lm/l (about 2ml/gallon)
Bio-Bloom: 2lm/l (about 8ml/gallon)

Day 30
Bio-Grow: 0.5lm/l (about 2ml/gallon)
Bio-Bloom: 3lm/l (about 12ml/gallon)

Day 34
Bio-Grow: 0.5lm/l (about 2ml/gallon)
Bio-Bloom: 4lm/l (about 16ml/gallon)

I tried to give as much info as possible. That's my third project and I never had so many problems...

Please, help. I really want to finish these Kali Mists successfully. Thanks :)

P.S. I came to a conclusion that the yellowing is caused by Potassium deficiency. Here is why:
P1000511.jpgcannabis leaf-deficiencies.jpg
What do you think?

If that's the case, should I start with the Green Sensation (NPK 0-9-10) on full dosage? How should I combine it with the Bio-Bloom?

Thanks again :)
 
lahadaextranjera

lahadaextranjera

Well-Known Member
Yes, they're def and u can see that clearly in pic 7. In the 5th week of flower they need more P & K. I can see that u can been adding slowly to ur feed. I would combine ur P K 0-9-10 with ur normal food as they look low on N too.

I don't use ur nutes so wait for someone else who does to advise u on the dose. Go easy and expect to wait a few days to see the buds swell and leaves colour up.
 
Alexander Supertramp

Alexander Supertramp

Well-Known Member
I see signs of both P and K deficiency. I have never used Green Sensation but it contains what your plants are looking for. Be sure to keep including a bit of your grow nutes as an N and micro source.......
 
P

Pathaway

Member
bird mcbride said:
Any chance they got overwatered?
Click to expand...
I doubt it.

I usually wait 4 days between waterings and I water when the plants start to droop a little.
As the RH is high I'm careful not to overwater, because I fear mold and fungi the most...
The grow is in a basement with very poor hygiene and very high RH (that's the price I have to pay for cooler temps in the summer).

I water with about 0.30 gallons of solution and the size of the pots is about 3 gallons.
 
P

Pathaway

Member
lahadaextranjera said:
Maybe the high RH is reducing transpiration and nutrient uptake.

Is there a good vent fan apart from the oscillating fan?
Click to expand...
The big oscillating fan is the only one in the basement. The pots are not in a box, but are just surrounded by a hanging white oilcloth.
The grow is in a spacious basement and from time to time I let fresh air in by opening the outside door.
 
I

IndigoMink

Member
I'm in my 4th wk of flower and my tips are yellow as well, no brown tho. Would love to hear what you resolved to do.
 
jpockets420

jpockets420

Well-Known Member
That is a P and K combo deficiency. I see traits of both deficiencies in your leaves. High humidity can limit the uptake of mobile elements. Get that humidity down!
 
lahadaextranjera

lahadaextranjera

Well-Known Member
Pathaway said:
I doubt it.

I usually wait 4 days between waterings and I water when the plants start to droop a little.
As the RH is high I'm careful not to overwater, because I fear mold and fungi the most...
The grow is in a basement with very poor hygiene and very high RH (that's the price I have to pay for cooler temps in the summer).

I water with about 0.30 gallons of solution and the size of the pots is about 3 gallons.
Click to expand...
I grow in an attic but use AC. My friends grow in a huge basement with the lights on at night to even out the RH- more constant temps result in less range of RH. They don't have AC, they pull in air from outside thru their garage which is also under the house. Is there no way you can build and out vent??

Ur not overwatering, but they are probably using the nutes much slower due to RH and therefore looking def. If the RH was 50-55% u'd be watering more often so in this case increase the feed to last the extra days.
 
lahadaextranjera

lahadaextranjera

Well-Known Member
Pathaway said:
I doubt it.

I usually wait 4 days between waterings and I water when the plants start to droop a little.
As the RH is high I'm careful not to overwater, because I fear mold and fungi the most...
The grow is in a basement with very poor hygiene and very high RH (that's the price I have to pay for cooler temps in the summer).

I water with about 0.30 gallons of solution and the size of the pots is about 3 gallons.
Click to expand...
Do u get a run-off with this amount of water?? Are you top-up watering due the the RH problem?
 
P

Pathaway

Member
Hi. I don't have much time now so I'll just post a new pic:
P1000625.jpg
Is this also deficiency? I have to know if it's mold or fungi. If it's not, I don't have to remove the leafs.

Thanks a lot for helping. I'll have a look at the posts later.
 
P

Pathaway

Member
jpockets420 said:
That is a P and K combo deficiency. I see traits of both deficiencies in your leaves. High humidity can limit the uptake of mobile elements. Get that humidity down!
Click to expand...
I'm trying to get it down. Yesterday it was around 70% which is much better than 95%. The plan is to put the dehumidifier on a timer and use it only in the dark period as than the humidity is higher. As of now I don't have an option to use the dehumidifier 24/7.
 
P

Pathaway

Member
lahadaextranjera said:
I grow in an attic but use AC. My friends grow in a huge basement with the lights on at night to even out the RH- more constant temps result in less range of RH. They don't have AC, they pull in air from outside thru their garage which is also under the house. Is there no way you can build and out vent??

Ur not overwatering, but they are probably using the nutes much slower due to RH and therefore looking def. If the RH was 50-55% u'd be watering more often so in this case increase the feed to last the extra days.
Click to expand...
Unfortunately, an out vent is not an option because It'll be visible from outside, but I can open the basement door more often with the fan blowing in.
As for the day/night period - I did the same. It's dark during the day and the light is on during the night.
 
jpockets420

jpockets420

Well-Known Member
Make sure you have a de-humidifier that doesn't have function lights. I bought one and realized that it had a red and blue light when it was powered on. I tried black finger nail polish..duct tape...nothing will de illuminate that power light lol. Something simple like that will produce mad hermies!
 
P

Pathaway

Member
Hi again. As you say that the P and K deficiency is caused by the high RH, does this mean not to give higher doses of P and K?

The plan is to give them higher dose of P and K:
Bio-Grow [NPK 8-2-6]: 1ml/l (4ml/gallon)
Bio-Bloom [NPK 2-6-3,5]: 3ml/l (12ml/gallon)
Green Sensation [NPK 0-9-10]: 1ml/l (4ml/gallon) - this is the manufacturer's recommended dose

Is it a good idea to use a little bit of Epsom salt? If yes, how much to dissolve?
I read in the forums and there are suggestions from 1/4 teaspoon to a full tablespoon in a gallon of water...

Thanks a lot :)

P.S. I used about 1 teaspoon of Epsom salt for 1 gallon of water.
 
P

Pathaway

Member
Hi. I watered with the above solution. I hope the plants will be happier now :)

Thanks everyone.

IndigoMink, I'll post the results here in a while.
 
You must log in or register to reply here.
Top