New Grower Problem With Plant?

[DarkOwl]

Hello All,

This is my first grow, the strain is NL auto it is now day 35 and I'm having troubling diagnosing the problem with my plant. For the last 5 days it has developed yellow leaves with brown spots that dry out, I have read in the forums about potential causes and thought it might be a Mg deficiency. I added 1/4 tsp epsom salts to 1L water and gave it to the plant. I would like to hear others thoughts of what it might be, thanks.

My Set-up
Soil
Dutch nutrient grow A&B 1/2 strength every second watering.
11L Pot
8 x 23w Cfl lights
Box is 30" x 17" x 60"
Walls covered in reflective sheets
Small fan
20/4 light cycle
Temps vary from 74-82 with lights on and 64-69 lights off
Nutrients bottle A N 2.00% soluble potash 2.00% Ca 2.00%
Nutrients Bottle B phosphate 1.00% soluble potash 3.00% magnesium 0.50% molybdenum 0.0011%

 

[Nam80232]

Grow room temp looks good, but what is the temp on the plant? Looks like your lights are very close to her. Very yellow leafs as well. Your new leafs seem to be clawing hard, and nitro will lock out mag. But that's just my 2 cents. I'm sure some one will be here soon. Have you posted this journal in the live help thread yet?

 

[DarkOwl]

Thanks for the reply Nam, this is the only place I posted.

 

[Nam80232]

I stuck a link in there for ya

 

[Nördlich]

I unfamiliar with those nutrients. Did you possibly start giving her blooming nutes too early? It almost looks like a lack of Nitrogen, but that's just a guess.

It also looks like a problem I had with overwatering one of my NL's last summer. I gave it way too much, no drainage where I had that one plant, and the roots started to rot. She pulled through, but the buds were really airy.

that is some nice sized growth for 30 days! Hope you get it all sorted!

 

[DarkOwl]

Nord, I have been giving it about 1L water every 3 days, no blooming nutes yet. So far I have gave it 1/2 strength bloom nutes 3 times.

 

[pop22]

I copied this from: Marijuana Plant Care
By Robert Bergman

Marijuana Nutrient Deficiency – Potassium

Potassium deficiencies in marijuana are somewhat common.
When using natural fertilizers like guano, you have to take into
account the fact that potassium is going to be the least abundant
of the three macronutrients (nitrogen and phosphorus being
the other two). A potassium deficiency might actually make the
marijuana plants appear taller and more vigorous at first glance,
but the bottom leaves might be dying. The leaves may also be turning a tan or brown color
and developing necrotic spots in some locations.
Chlorotic spots will start to show up as the deficiency persists. Slow growth and smaller
growth are all possibilities with a potassium deficiency. Potassium is important in the
transport of water and the development of buds later on. Even so, small deficiencies are
really only cosmetic. Fixing larger deficiencies takes a water-soluble fertilizer that is high in
potassium

 

[Renaissance Redneck]

Evening DarkOwl.
Let's start with some basic info.
1) What are your pH levels looking like pH of water before and after adding nutes, and your run off pH.
2) What's your humidity at?

 

[DarkOwl]

The Ph level is around 6.2 -6.7 and current humidity is 63. I have never added enough water at one time to have the runoff needed to test the Ph.

- - - Updated - - -

I copied this from: Marijuana Plant Care
By Robert Bergman

Marijuana Nutrient Deficiency – Potassium

Potassium deficiencies in marijuana are somewhat common.
When using natural fertilizers like guano, you have to take into
account the fact that potassium is going to be the least abundant
of the three macronutrients (nitrogen and phosphorus being
the other two). A potassium deficiency might actually make the
marijuana plants appear taller and more vigorous at first glance,
but the bottom leaves might be dying. The leaves may also be turning a tan or brown color
and developing necrotic spots in some locations.
Chlorotic spots will start to show up as the deficiency persists. Slow growth and smaller
growth are all possibilities with a potassium deficiency. Potassium is important in the
transport of water and the development of buds later on. Even so, small deficiencies are
really only cosmetic. Fixing larger deficiencies takes a water-soluble fertilizer that is high in
potassium

So my nutrients don't have enough potassium? what is a good substitute? Thanks.

 

[Nam80232]

Ok, I'm going to compound the possible problems, and I'm sorry. But it might be worth thinking about. Without watering till runoff you might have a salt buildup on top of what ever may be at the "root" of the problem. Sorry a little bit of a pun there. Just something to keep in mind. Salt buildup on and around the roots will lock out nutes causing all sorts of problems I.e. Yellow leafs telling you not enough n, while causing the classic leaf claw telling you too much n. Send mad amounts of karma your way.