Yellow spots on leaves

Kefka666

Active Member

• Jan 16, 2008

• #1

There are yellow spots on some of the leaves of a plant, and I can't think of what's causing it.

Light: CFLs.
Water: distilled.
Fertilizer: 3-3-3 all-purpose liquid organic fertilizer with multiminerals. Diluted it in distilled water and ph-adjusted it 7ish with dolomite lime pellets dissolved into mixture. Using every several days in low amounts.
Temp: ~80-88 °F, soon to be lower.

Two of the following four pictures display the spotted yellow leaves, one shows a slightly wrinkled/regular leaf, and the other the top of the plant.

 

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BSIv2.0

Well-Known Member

• Jan 16, 2008

• #2

What nutes are you using?

Looks like mg deficiency at 1st glance. Im not a big fan of distilled water if you're not positive you're feeding the micro nutrients that are in tap water....JMO.

Try using regular tap water....or adding some dissolved epsom salt to your plain water feedings for a while.

If your're NOT feeding them....it could be just low on Nitrogen.

 

Kefka666

Active Member

• Jan 16, 2008

• #3

The fertilizer is a 3-3-3 all-purpose organic fertilizer with multiminerals. Diluted it in distilled water and ph-adjusted it 7ish with dolomite lime.

 

BSIv2.0

Well-Known Member

• Jan 16, 2008

• #4

Just try the epsom salt and see how it goes.

 

Kefka666

Active Member

• Jan 16, 2008

• #5

Here's another unhappy lower leaf.

 

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Kefka666

Active Member

• Jan 16, 2008

• #6

Update: I fertilized and watered lightly this morning after posting and it seems that the yellow spots have spread to another leaf by this afternoon. Whether or not this is related I do not know. Also, I've noticed that some of the leaf tips are curled downward.

I have never seen this degree of necrosis in Magnesium deficiency, so it leads me to suspect that something else or additional is at work. Any further thoughts? Thank you in advance.

 

stamb

Active Member

• Jan 16, 2008

• #7

Hi man. I have the same problem. Just fix PH level... The plant cannot absorb the nutrients... If you think that it's not the ph problem...
Hmm this link is very very helpful...
International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles!

 

Kefka666

Active Member

• Jan 16, 2008

• #8

In which direction? Do you think the pH is too high or too low?

 

Joesmithofcourse

Active Member

• Jan 16, 2008

• #9

From what I have read you probably want that PH level around 6.5 maybe a little lower. Again that is just from what I have pulled from reading posts here on this site.
I had some PH issues when mine was over 7 so I took it down to about 6.5 and things are better. I didn't have yellow leaves I just had some folding and curling and I still do not know if it was over watering or PH but I have since lowered the PH and water about every 3 days and they seem to be doing much better.
Just my 2 cents.

 

Kefka666

Active Member

• Jan 17, 2008

• #10

Thanks for the advice. Still, I find this pretty strange since the pH of the fertilizer water is approximately neutral (using alkacid paper to test, so ±1 pH) and the pH of the distilled water is the same. I'd be surprised if the fertilizer-lime-water was >7 pH, but it is possible, given the precision limitations of pH paper. Opinions?

 

stamb

Active Member

• Jan 17, 2008

• #11

PH paper isn't accurate.. Get a fluid PH tester for aquarium atleast or digital. Digital is the best but it's very expensive.