Plants Yellowing!

For about 10 days now, my plants have begun to yellow at their top.

Now, they've yellower all around and the edges of some of the leaves are more so than the rest.

I thought it was the lights so I placed them higher up.

I feed them a good amount of Bio-Grow.

Also, they don't seem to be growing anymore.. They reached my Scrog screen and sort of stopped..

I'm really worried!

What could be causing this?

They dont look *terrible*, but that is a bit more yellowing than you should be seeing this early in the plants life. Im not very experienced, but I would say that looks like Nitrogen Deficiency. Is your feed high in Nitrogen?

Hopefully some others will chime in soon too, just in case im derping up lol

Did you feed them before or after this problem started?

Diabolical666 said:

Did you feed them before or after this problem started?

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I can't recall if this started happening before I started using Bio-Grow or not, but it doesn't make sense for the nutes to cause this, right? This looks more like a nutrient deficiency.

All I know is the Bio-Grow is not helping. Perhaps I should flush them..

ok I looked up that bio grow...it has no npk. I thought maybe with the word "grow" in it it might have high npk. But its a molasses beet sugar. Stop using that crap imho. Your plants need nutrients NPK. Cannabis is a very hungry plant especially in flower. They need fed weekly. Make sure your ph is 6.5-7 so all nutrients are available and feed the suckers

I'm not sure exactly what your issue is. Nitrogen deficiencies will start at the bottom of the plant, not the top. The deficiencies that start at the top of the plant, but not on the new growth points, are: sulfur, copper, iron, manganese. Calcium and born start at the new growth points. Not sure if this will help or not, but the location of the yellowing is worth noting.

See a couple leaves with mottled color and leaves pulling to one side. Good to pick these off and scope with 100X for broad mites. Probably nothing but I would not leave those on the plant in case they are colonies building up.

Diabolical666 said:

ok I looked up that bio grow...it has no npk. I thought maybe with the word "grow" in it it might have high npk. But its a molasses beet sugar. Stop using that crap imho. Your plants need nutrients NPK. Cannabis is a very hungry plant especially in flower. They need fed weekly. Make sure your ph is 6.5-7 so all nutrients are available and feed the suckers

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I've been using bio-grow(bio bizz) products for a while. It definitely has NPK. See photos. I've always heard that bio bizz products are naturally low in cal and mag. I would more research around calcium and magnesium defs and decide for yourself. But to me it sounds like you need some calmag. Check this site out. http://www.growweedeasy.com/marijuana-symptoms-names

Triplec said:

I've been using bio-grow(bio bizz) products for a while. It definitely has NPK. See photos. I've always heard that bio bizz products are naturally low in cal and mag. I would more research around calcium and magnesium defs and decide for yourself. But to me it sounds like you need some calmag. Check this site out. http://www.growweedeasy.com/marijuana-symptoms-names

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I don't know, man. I used Bio-Grow on my first grow and I had the same issues.

I think I'm going to go back to using GH Flora. I didn't have this issue then.

Dyna

Trackr said:

I don't know, man. I used Bio-Grow on my first grow and I had the same issues.

I think I'm going to go back to using GH Flora. I didn't have this issue then.

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I've got the whole arsenal of BioBizz products. I'm pretty invested at this point. Changing nutes for me would be another big research project and more money to spend. I still think you got a cal or mag def though.

thats def cal and mag def...the light green and taco leaves are from mag and you can foliar feed with epsom salt a couple times and it will green em right up..the spots and yellowing ends are cal def starting and its from either nute buildup, not enough cal or usually low ph..not sure if you can foliar with cal mag but you should if you can and it will slow it a lot..ive had it a few times through flower and it doesnt affect the buds at all you just have to keep up on it till the end

Dyna and mag pro 10 bux a peice chelated and the fact that they have all micro and macro nute's in there w/o them locking something out is a testimony to quality....I have had no prob's w/ it and I love the fact that I have seen result's equal to and better then any other multipart nute system
Heres a link to some comparison's done by another member....I have also found his claim's about no need to PH my water to be true the solution in 20%tap x R/O keeps me right around 6.0 PH
https://www.rollitup.org/t/dyna-gro-vs-general-hydroponics-dumpster-grow.358562/
https://www.rollitup.org/t/dyna-gro-vs-advanced-nutrients-connoisseur-ak47-grow.429438/

Good news is that the plants still look good. Bugeye gave you some great info.

Looks like a nutrient deficiency to me. I use Cal-Mag, micronutrients, and sulfur with every grow because my regular nutrients and soil don't seem to have enough. You might also check your pH and TDS.

Trackr said:

For about 10 days now, my plants have begun to yellow at their top.

Now, they've yellower all around and the edges of some of the leaves are more so than the rest.

I thought it was the lights so I placed them higher up.

I feed them a good amount of Bio-Grow.

Also, they don't seem to be growing anymore.. They reached my Scrog screen and sort of stopped..

I'm really worried!

What could be causing this?

Click to expand...

Your scrog does not look that bad to me, but it looks as though the light (???) may have been a bit close. Do you add "vitamins" (B1 thrive, Magical, Sugar Daddy) to your ph'ed nute mix or watering? I see curling in some leaves too. Good luck! Peace

From experience I would say most likely low ph. Either phosphorous or potassium begins to lockout around 5.5 which causes the yellowing between the veins of the leaves. The discoloration of the small dots on the leaves is also indicative of low ph.
I'd test the runoff and if it is under 6 you should probably try to raise it or add a lime buffer.
I'd slightly increase the ph of my water by about 1-2 points a watering until it is around 7.5-7.6 going in and 6.0-6.5 coming out. Of course if 7.6 causes 7.2 runoff then decrease the ph of the water going in.

Sometimes the runoff/soil can be 5.0-5.9 and the plant can still thrive in organic conditions.