My Magnesium hell!!

So as mentioned I've been having an issue with magnesium def, posted a thread on here thinking it was manganese apparently not. Anyway had that during late veg stage used epsom salts and it cleared up nicely, now i'm 4 weeks into flower and its back again, epsom salts aren't working tried root feed and folair also used canna mono magnesium and also flushed through. None of which is making a difference, was advised to drop ph down to 6.2-6.4 for a week and still nothing!! About to flush again tomorrow (with ph'd water or no?any views?) Its starting to get pretty bad and I've lost a few leaves now! Any help much appreciated guys!

You are looking N deficient, Sulphur, Iron, zinc, magnesium, and calcium will green her up. Try watering with a veg solution and increase cal-mag

Are you feeding any nutes?? She looks hungry to me...

I am always very cautious when "fixing" plant problems. Only try one thing at a time, go real easy when adding anything. Make real sure your water is ph'd.

Are you sure it's mag def. from the pics, looks like lower fan leaves are yellowing, I would think N def.
I am interested what others have to say.

Good luck.

yes just fed today using bio bizz grow,bloom,top max and algamic any suggestions on calmag products for soil my local shop only has the sensi veg and bloom stuff?

Well i was told to drop the ph a little to maybe give them some manganese but that hasn't worked so maybe give them some more bio grow than i have been? ive been sticking to their recommendations but a friend of my said to double whatever they tell you I've always been a bit scared too and maybe that's my downfall?

That's a simple nitrogen deficiency. If that were my plant, I would feed it some fish hydrolysate (I grow organically).

If you're going the chemical route, give it a feeding of 1/2 strength of your veg nutrients PLUS 1/2 strength of your bloom nutrients.


STOP hammering them with magnesium. It's just going to cause problems and lock other things out.

Would you suggest flushing them with 1/2 strength nutes as i just gave them a full feed this morning?

No flushing needed. Did you give any veg nutrients? If not, just do it next watering. Your yellowing leaves won't repair themselves, but you can stop the progression of the yellowing and help the plant finish strong.

Lots of people end up with nitrogen deficiencies around 4 weeks in because they immediately switch to "bloom nutrients" when they change the light cycle. In reality, plants need LOTS of nitrogen during the first few weeks of bloom. Think about it. The plant doubles or triples in size during that first few weeks, and it's still producing new leaves and stems. This crazy burst of veg growth requires lots of nitrogen.

"N" toxicity presents it's self with dark color leaves and that the leaves look like a claw, generally once one sees a nutrient deficenty you are all ready 2 weeks behind in fixing the problem, flush flush for 2 weeks

harris hawk said:

"N" toxicity presents it's self with dark color leaves and that the leaves look like a claw, generally once one sees a nutrient deficenty you are all ready 2 weeks behind in fixing the problem, flush flush for 2 weeks

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Why would you recommend this guy flush for two weeks? This is not toxicity... The plant just needs a little nitrogen, that's all. No need to over complicate it.

my plant was looking looking slightly like this during but in veg, i personally would try hit a ph of 5.8-6.0 and flush any salt build up by flushing, i went to flushing every 3 days and use [h=1]Plant Magic Magne Cal+, and stick to this for atleast a week before thinking its not working[/h]
am not a pro and just a beginner but worked for me

I agree with giving grow fert. And also yes plants can run out of N during bloom. I give mine grow fert every once in a while during flower for just this reason, plus it avoids over bloom ferting...

Simple Nitrogen deficiency. Nothing to worry about at all. It is perfectly natural for the plant to use up all the N in the soil and start to pull it from the leaves. No need to flush. back off a little on the Cal-Mag and give her 1/3 grow formula and 2/3 bloom formula next time you water. Don't be alarmed when this keeps happening. The bottom leaves ALWAYS yellow and fall off in the final 2-3 weeks. If you try to prevent this from happening by giving her more N, then she will still be full of N when you go to smoke her and you certainly don't want that. Remember, the plant is reaching the end of its life cycle (in the final weeks before harvest) and is preparing to die of old age. Nothing dies of old age looking young except nasty old movie stars.

harris hawk said:

"N" toxicity presents it's self with dark color leaves and that the leaves look like a claw, generally once one sees a nutrient deficenty you are all ready 2 weeks behind in fixing the problem, flush flush for 2 weeks

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that made no sense. he doesnt have a toxicity its just yellowing because hes got a few weeks left of flower and it wants more nitrogen.

Well cheers for the help guys, in week five now of a 7-8 week finish strain just going to leave the girls to sap the last of the nitrogen and hopefully have some lush tasting smoke!

Are you using RO water? Have you been feeding them? Did you put garden lime in the soil? If you are using RO or distilled water of some sort are you putting calcium mag back into the water?
Are you watering them enough?Is there good air exchange?, its not in a sealed room where it will run out of co2 to breath is it?
Are you using well water or city water?
What kind of soil are you using?
What are your room temps and humidity ?
The more information you can give about what is going on the easier it will be to make a determination on what the problem is.
Right now it stands these are your problems..
It could be a lack of nutes..it could be a lack of calcium . It could be a PH problem.It could also be a lack of air exchange in the room.It could be something toxic in the room made out of plastic(not likely)It could be not getting enough water.(not likely)Or it could be several combinations of all listed

Just using normal tap water, been feeding every couple of days, wish I did put garden lime into my soil, haven't been using cal mag but think i pick some up for next grow! Has adequate fresh air intake, city water, using plagron light mix and temps average 27.6c and humidity average 50%- think I got everything?!

It's because ... flushing cures all!!!

Flushing and starving babies is what weed growing is all about.

Just feed them ... nothing... for a month and they'll recover. No food because they'll burn.. no water because they'll be overwatered. Wait for all the leaves to turn yellow and the new growth to come in retarded before you start feeding a 1/256th strength solution, then up it to 1/128th strength after 2 more weeks.

And never cut off the roots... THC COMES FROM THE ROOTS.

(sarcastic post.. do not take advice from this post)

SpicySativa said:

Why would you recommend this guy flush for two weeks? This is not toxicity... The plant just needs a little nitrogen, that's all. No need to over complicate it.

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