Magnesium Deficiency?

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stoneylove

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Read through all the troubleshooters and I think this is Mg def. However, I would love it if someone could confirm or refute that conclusion. :ignore:

It does not effect all the leaves and seems to slowly creep up. It starts as a little brown spot or blotch. More little spots begin to appear and grow in size. The plant is about 3 weeks old. Soil is a blend of local nursery organic, scotts topsoil, perlite, and probably not enough horticultural limestone. Thanks for the help.

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Hey Stoney, what strain are you growing? I got sone northern lights and its doing the same thing, only in hydro.
 
3 weeks old something is definantly going on imo. Was any of that soil have nutes already in it? What strain? Besides the brown spots they might look a little overwatered hard to tell. I never seen brown spots like that but more info would be good. Have you used nutes yet?
 
Growing northernberry and skunkberry and it seems to effect both. Virtually the exact same thing happened with my bagseed grow that was in scotts topsoil but not to the plants in pre-nuted miracle grow, so thats why I dont think it is an n-p-k problem.

As far as overwatering, I water them about once-twice a week, in 3 gallon containers. These hadnt been watered since wed. morning, or 5 full days. That wed. watering was the first nutes, organic 5-2-5 (blue mtn. on ebay). I gave them some epsom salts and it seems like the spots have slowed, but I wanted another opinion on the cause because it seemed like the spots slowed on the bagseed and then have spread like mad near the end. Trying to avoid that outcome with this grow.
 
same here, started with spots then half way through flower it just took over everything. i thought it was a mag def too, used epsom salts, but it still didnt control it. must be the water.
 
I use distilled water from menards, walmart, grocery store, etc. No tap water at all. And my crappy pH meter says 6.8. If I remember right soil should be 6.5-7 pH.
 
Im no pro, but that looks N def, what are you using for nutes, and is your soil nute fortified or a soil less medium?
 
This is just what I think, but it seems a bit early to be having a Magnesium Deficiency. More likely a combination of not enough light and Nitrogen?. Not sure with the limited amount of information that is been supplied.
 
Not sure what other info to provide, so here goes:
400w hps (50,000 lumens) about 18" away.
4 23w 6500K cfls (1600l each, 6400l total) about 3" at the closest points.
2 23w 2700k cfls (3200l total) finishing up my last bagseed autoflower. Probably 2 more weeks.
Room 3x3.5.6=10.5 sqft.
Thats 59,600 lumens over 10.5 sqft, or 5676 lumens/sqft.

Temps are between 74-79 w/lights on (depends on basement temp) and get down to 67 w/lights off.

And I fed a week ago w/5-2-5 organic nutes. At that time I also used about .5tsp of epsom/gal water on the plants showing spots. I never used epsom, or any mag supplement, on my bagseed. The spots on her seemed to slow w/the chem nutes I used, and she def'n got greener, but they have definetly spread. Thus, I am inclined to dismiss N def. as the reason for the spots.
 
This is not a deficiency, I think its a burn. Flush those poor babies and lemme know the runoff pH. Thanks man.
 
My nute feeding was a mix of veg nutes and a Tonic.
Organic Veg Nute: 5-2-5,
"The ingredients are Artesian Spring Water, High Nitrogen Bat Guano, Worm Castings, Coral Calcium, Unsulphured Molasses, Humic Acid, Beet Root Extract, Comfrey Hay Extract, Alfalfa Meal Extract, Endo and Ecto Bacteria."

Tonic: 1.25-.4-.9, I believe this is what is known as an "activator" in organic growing. I'm a newb though so please correct me if I am wrong.
"This tonic contains the following : Artesian Spring Water, Worm Castings, Mycorrhizal Fungi, Coral Calcium, Unsulphured (Blackstrap) Molasses, and Humic Acid derived from Oak Leaf & Peat Compost."
 
I just checked the pH with my meter and it sits about 6.7.

And the leaves most effected are curling upwards. I believe it was HIE's troubleshooter that used the phrase "praying for magnesium."
 
Its is my understanding that during flowering is the most likely time to experience magnesium deficiency.
 
Yeah, seems like nothing you used would have done anything bad.

If it is magnesium, add a little epsom salts (magnesium sulfate) to next watering. Should make em happy :).
 
Just wanted to give a quick update on this issue so hopefully someone can use it in the future. It appears that this was a Mg deficiency. I used about 1/3 tsp. of epsom per gallon of unchlorinated water in each of the last two waterings and the brown splotches have not spread to the new leaves. The old, effected leaves curled upward and dried out. I removed the dead parts because they were starting to curl over-top of the new growth. But I dont see any new brown spots at all. :headbang2:
I have eight plants that were all effected to varying degrees and they all appear healthy now. Too bad I wasted two weeks of growth but I learned a great lesson here. :farm:

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At least your prob started early, i have 2 girls, 30 days into flower and they are starting to get taken over by the brown creep. but nothing i do seems to stop it, so consider yourself lucky. Good Luck Stoney.
 
smoky anda bandit said:
At least your prob started early, i have 2 girls, 30 days into flower and they are starting to get taken over by the brown creep. but nothing i do seems to stop it, so consider yourself lucky. Good Luck Stoney.

Whats the Brown Creep? :confused:
 
its what was happening to the leaves on my plants. it starts out as a couple brown spots and then creeps up the whole leaf, turning it brown. The brown creep i call it.
 

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