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Leaf problem, nutrient def?


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Hello all at 420 ;)
Im having some trouble with my plants, i have grown these plants in 6 months now and i cant for my life figure out wtf is going on. I have tried going up in EC and down but no difference.

I have a Rolling SOG each week setup, week 1 and 2 is connected to the Vegetative water supply, 3 and 4 have flower nutes and so on

The problem i have is that as soon as two weeks have gone bye the plants look GREAT, nice leaves nice color, no sign of problem at all. Then i move them to the new flower nutrients and thats when shit starts to hit the fan.
the pictures below from flower shows u what i mean. The edges is crispy all over the plant and starts to yellow, leaf stems are brittle. They will survive to the 9 weeks they require but only Yield very poor looking buds :(

Then there is the BB motherplant that has some of the same look but looks more like Mg deff, but have tried adding Mg but dont fix it.
Mother has EC of 0.3

Any help would be apreciated, i can upload more images if u want them in white light.

Thanks in advance

DP Blueberry and Bagseed sativa
3 plants ech week rolling SOG
Hydro Ebb & Flood, (15 min on 45 off)
Canna Aqua + Flores
Water from the city, 0,1EC very good

60L for 6 plants
Water Temp ( 20-22*C, 68-72*F )
PH of water between 5,5 and 6,5
EC Veg 0.9, flower 1,1-1,3

600w HPS on 3x3 sqfeet, cooltube 10 inches from plants
room temp Vegetative is 26*C = 79*F
room temp Flower is ~30*C = 86*F

Humidity Veg 40%, Flower 30

Mother problem ( DP Blueberry )

Flower problem ( some bagseed Sativa strain )


Member of the Month: Jan 2012
Hi puleboll ~ Its could be many things going on there could be Mg deficency :

The lower leaves and later the middle leaves. develop yello patches between dark green veins. Rusty brown spots appear on the leaf margins, tips and between the veins, as the deficiency progresses. The brownish leaf tips usally curl upwards before drying.

Magnesium can be locked out for a few reasons the root enviroment is to wet and cold or acidic and cold. Magnesium is also blocked if there is an excess of potassium, ammonia (nitrogen) and calcium (carbonate). Or simply there is not anoth magnesium to supply a heavy demand.

Treating Mg def.

I believe that "room temp Flower is ~30*C = 86*F" to be slightly high and light a little bit close!

Heat stress
Leaf fringe standing up - leaf fringes that point up mean that the leaf is trying to dissipate as much moisture as possible, but it is unable to. This could be because of toxic salt buildup, lack of water, or heat stress.

Hope you sort out your problem buddy.


New Member
Hello GodSpeed, ty for your advice

The 6 plants in flower only gave 30-40g of bud, and not very nice either :/

Magnesium def was spot on for the BB mother, fixed it with Canna Mono(7% MgO)
but am unsure why the problem arose, does some strains require more Mg than others? and is there like a paper i could read on cannabis nutrients and what the plants want in different stages? i know there is no "exact" measurement, but there got to be some generalisation :)

I put the old mother into the flower room, and now after 2 weeks, she also experiences the same symptoms. I have fed her Canna Mono (7% MgO)
10ml in the tank and that seemed to stop the progress but not fix it, how high can i go before i overfert with Mg?

Oh, and finally there is another defiency starts at the tips and looks dark grey necrosis, will post pictures below :)

Thank you again, its nice to get advice like this, helps to calm me down on my first hydro grow :)

raised light 5 inches
lowered flower temp 10 degrees F (winter weather is good for something finally ;) )


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