Lower Leaves Yellowing with some Brown Spots

darren_21

Active Member
Tomorrow will be 3 weeks into flowering. There seems to be some yellowing of the leaves starting at the bottom of the plant. There are also some brown spots.

I use DNF Nutrients every other watering and I water every other day (up from every 3 days during veg). I have yet to use the Bloom Fortifier (0-50-30) nutes also from DNF. I was planning that for next feeding.

I use regular tap water.

PH level of the soil is good.

Inside the box I have mounted a 400w HPS with reflector. Exhaust setup to vent outside.

Current temperature is 20°C, humidity is 35%.

Any help would be appreciated,
Thanks
 

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smokeybandit22

Well-Known Member
what up D, lookin glike u got a K deficiency. I have posted about 6 times today and yest in this section for peeps with the same issues, 3rd week flowering. very noticble from the 2nd and 4th pics-slight chlorosis first, followed by necrotic leaf edges and random spotting on seemingly unaffected leaves. have u flushed recently? now would be a good time for those super bloom ferts but I would go with 1/4 to 1/3rd dosage as those are some very high PK ratios. still looking ok, very common for plants to go K deficient first half of flowering. also, did u have any of these problems before u started watering more and why did u start watering more if they were ok before? I would go back to how you were or at least split the diff. overwatering will cause nute uptake problems as well, so something else to keep in mind
 

darren_21

Active Member
The increase in watering was due to a very noticeable increase in water intake when I went into flowering. I have been watering every other day for 2 weeks now. I think you're right when it comes to the deficiencies. I was waiting until this point for the bloom ferts and like you say, that seems to be my problem. I will go ahead with these ferts next and see how things turn out. Thanks.
 

Uncle Ben

Well-Known Member
Tomorrow will be 3 weeks into flowering. There seems to be some yellowing of the leaves starting at the bottom of the plant. There are also some brown spots.
Sure sign of a N deficiency, NOT a K deficiency. Contrary to popular belief, cannabis does not require alot of K. I blend my own potting soils, use blood and bone meal for N & P respectively, and never add anything that is rich in K. They get plenty from the peat, compost, and sometimes horse manure I use.

Get off the Bloom food love affair, those foods ALWAYS do more damage (by inducing premature leaf drop) than good. A NPK value of 0-50-30 is outrageous.

Good luck,
UB
 

Tdawg

Active Member
k so i started my first plant its a couple weeks in and the leaves have these yellow and brown spots on them but its only on the first set the second set only has like one small spot any help? i have pics but i dont know how to add them on here so any points on that could help to lol
 

ganjafarma808

Active Member
The same thing is happening to my plant. Today I noticed random spots and before that noticed the yellowing of lower leaves.

I plan on flushing my next water. You should probably do the same :bigjoint:
 

smokeybandit22

Well-Known Member
Sure sign of a N deficiency, NOT a K deficiency. Contrary to popular belief, cannabis does not require alot of K. I blend my own potting soils, use blood and bone meal for N & P respectively, and never add anything that is rich in K. They get plenty from the peat, compost, and sometimes horse manure I use.

Get off the Bloom food love affair, those foods ALWAYS do more damage (by inducing premature leaf drop) than good. A NPK value of 0-50-30 is outrageous.

Good luck,
UB
lmao, ur post is a joke. flowering plants use ALOT of K, just b/c ur plants dont, does not mean this is the norm. get a clue. most commonly, N deficiency is mistaken for K deficiency in early-mid flowering.
would love to see ur evidence or research support your ridiculous claims.
but, I doubt that since it is untrue. please prove me wrong. or dont post stupid stuff.
 

darren_21

Active Member
Hmm interesting...

Ok well I think I'm going to agree with smokeybandit on this one... From all the reading of done before I started this little endeavour (probly 10-15 hours of online research) this does make sense (the K deficiency). And it only furthers to convince my current suspicions...

I will be checking my plant shortly if they need watering I will be adding the bloom ferts for the first time. And yes, no worries, I will start LOW! lol

Will update as I see any changes.

Thanks!
 

Uncle Ben

Well-Known Member
Hmm interesting...

Ok well I think I'm going to agree with smokeybandit on this one... From all the reading of done before I started this little endeavour (probly 10-15 hours of online research) this does make sense (the K deficiency). And it only furthers to convince my current suspicions...

I will be checking my plant shortly if they need watering I will be adding the bloom ferts for the first time. And yes, no worries, I will start LOW! lol

Will update as I see any changes.

Thanks!
Good luck.
http://www.ces.ncsu.edu/depts/hort/consumer/quickref/fertilizer/nutri_def.html
 

darren_21

Active Member

Let me quote from your source...

"[FONT=Times New Roman, Times, serif]Potassium (K)"

"Deficiency:
[/FONT][FONT=Times New Roman, Times, serif]Reduced growth; shortened internodes; margins of older leaves become chlorotic and burn; necrotic (dead) spots on older leaves; reduction of lateral breaks and tendency to wilt readily; poorly developed root systems; weak stalks[/FONT]"

"
[FONT=Times New Roman, Times, serif]Comments: [/FONT][FONT=Times New Roman, Times, serif]High N/low K favors vegetative growth; low N/high K promotes reproductive growth (flower, fruit); calcium excess impedes uptake of potassium"

[/FONT]Thank you for the info!!
 

Uncle Ben

Well-Known Member
I have been posting in many cannabis forums for over 10 years, and one of the most common issues I see is folks using a food that is too high in K, these are mostly "cannabis specific" foods from firms like canna, AN, GH, etc. There is an affect called "element antagonism" which means that too much of one induces a deficit of the other. Take too much K for example, like a 3-6-10. It will induce a deficiency of Ca, Mg, and N which WILL induce leaf yellowing and spotting, the precursor to leaf necrosis.

Here's a ditty I wrote many years ago regarding the abuse of Bloom foods: https://www.rollitup.org/marijuana-plant-problems/158144-never-ending-abuse-phosphorous-bloom.html

Here is an explanation of the concepts I'm talking about with a chart. Recommend you file this in your bookmarks: http://www.totalgro.com/concepts.htm

Having said that, as mentioned in my archive, one of the best bloom foods on the market is Peters Blossom Booster, 10-30-20, although still a little high in P than it needs to be, it's a great food to have around in your cannabis toolbox.

Good luck,
UB
 

darren_21

Active Member
I have been posting in many cannabis forums for over 10 years, and one of the most common issues I see is folks using a food that is too high in K, these are mostly "cannabis specific" foods from firms like canna, AN, GH, etc. There is an affect called "element antagonism" which means that too much of one induces a deficit of the other. Take too much K for example, like a 3-6-10. It will induce a deficiency of Ca, Mg, and N which WILL induce leaf yellowing and spotting, the precursor to leaf necrosis.

Here's a ditty I wrote many years ago regarding the abuse of Bloom foods: https://www.rollitup.org/marijuana-plant-problems/158144-never-ending-abuse-phosphorous-bloom.html

Here is an explanation of the concepts I'm talking about with a chart. Recommend you file this in your bookmarks: http://www.totalgro.com/concepts.htm

Having said that, as mentioned in my archive, one of the best bloom foods on the market is Peters Blossom Booster, 10-30-20, although still a little high in P than it needs to be, it's a great food to have around in your cannabis toolbox.

Good luck,
UB
Interesting... I will definitely consider this information.

Maybe you can give me some input on what I'm using here. DNF nutrients were recommended to me by a good friend.

Currently using 2 bottles (equal parts):
BLOOM Part A 3 - 0 - 3 (Liquid)
BLOOM Part B 1 - 0.5 - 3 (Liquid)

Bloom Fortifier 0 - 50 - 30 (powder)

Nutes get added every other watering and the fortifier is supposed be to be once a week. With the information provided, this would seem to me that I should have a good balance all around, and the bloom fortifier should be making up the lack of P in the liquid formulas.

The pictures shown are from before I used the fortifier (which was last night)

Thoughts?
 

Uncle Ben

Well-Known Member
Interesting... I will definitely consider this information.

Maybe you can give me some input on what I'm using here. DNF nutrients were recommended to me by a good friend.

Currently using 2 bottles (equal parts):
BLOOM Part A 3 - 0 - 3 (Liquid)
BLOOM Part B 1 - 0.5 - 3 (Liquid)

Bloom Fortifier 0 - 50 - 30 (powder)

Nutes get added every other watering and the fortifier is supposed be to be once a week. With the information provided, this would seem to me that I should have a good balance all around, and the bloom fortifier should be making up the lack of P in the liquid formulas.

The pictures shown are from before I used the fortifier (which was last night)

Thoughts?
Too much P.
 

Uncle Ben

Well-Known Member
These numbers a little better UB? Thanks
A 1-3-4, when it's obvious you have a lack of N and have been hitting them with a NPK that is high in K? I guess my points in post #13 and links didn't register, oh well. It's a beautiful plant that is destined to lose the very unit that makes your buds.

Good luck,
UB
 

laserbrn

Well-Known Member
These numbers a little better UB? Thanks
Other than the slight yellowing on the lower leaves the plants look great. I would suggest that WHATEVER you decide to do to try to correct it, you don't overdo it. That's the most common mistake if you really want to get into what the most common mistake is.

It doesn't look like an N defeciency as N defeciency in my experience starts at the VERY bottom and leaves die off before it really has a chance to spread. It sort of eats one leaf at a time at first and then spreads more rapidly.

Good luck, I hope you get it figured out, but I wouldn't even 'freak out" over it.
 
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