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Nutrient burn?

Thread starter #1
I’m getting a lot of people saying it’s the heat or over feeding but I’ve researched and I think it’s nutrient burn, I use coco blend and my mix is 25L water and 35ml of each CANNA A and CANNA B. My plants are 5 weeks old and still in the vegative stage, can’t anyone help me with treat or even just to make sure it’s defiently nutrient burn, thank you
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Well-Known Member
Pix with lights off would be a lot more helpful. Turning them off long enough to get a shot or two won't hurt. Nute burn shows up as yellow/brown discoloration on the very tops of the leaves, usually more prominent on tender new growth. Difficult to tell with your HPS blazing.

How do the leaves feel; limp and flaccid or stiff and leathery? You say coco mix. Do you know the other ingredients?


Well-Known Member
What is your watering schedule? Is you grow medium prepackaged or a home blend? Interested in knowing what the other ingredients besides coco are and in what ratio if you know.
Thread starter #8
It is packaged mate I don’t know the full ingredients but if you go on the growell website and find the coco medium that’s the one I’m using, also I feed them once every 24 hours


Well-Known Member
Checked the grow medium. It's golden. Some have a heavy mix of nutrients in them but that's not the case with what you're using. 70/30 coco/perlite is spot on. Good choice.

The tips are indicative of some very minor nute burn. Of greater concern to me is the "clawing" of the leaves; downward drooping, limp looking and curling under. I'm familiar with two situations that can cause these symptoms, however, there may be more that I'm not aware of.

First is overwatering, but it's nearly impossible to overwater a plant at this stage in a good mix of coco/perlite like you're using. So let's rule this one out.

The second is nitrogen toxicity. It displays the symptoms you're experiencing plus the older foliage is abnormally dark, something I can't discern for sure from the pix. You appear to be feeding at about half strength and this makes me a little dubious about a nitrogen toxicity diagnosis. However, with it exhibiting some minor nute burn symptoms, I think our best course of action would be to discontinue nutes for a few days. Continue your present watering schedule with just water and observe the posture of the plant.

Don't expect the burnt tips to regain color. If new leaves come in uneffected and your foliage appears to perk up a bit you'll know you're on the right track.

Also, temporarily raise the lamp up a bit. This will keep the plant from working so hard while it's sick and concentrate on healing itself rather than struggling to put on rapid new growth.

Good luck


Well-Known Member
That is unfortunate. When you water/feed, do you water to waste? In other words, water until you get significant run off from the drain holes?

If your pots are portable, probably be a good idea to do a good flush. Carry them outside and run a good amount of water through them. Our coco guru here advises using three times water volume for an appropriate flush if I remember correctly. Use three gal water if in one gal pots etc. this will be a bit time consuming since you'll have to water slowly to avoid floating the coco/perlite out.

If we're on the right track, this will get the offending nutes out of the system quickly and plants should recover faster.
Thread starter #13
Okay they are in 23 litre pots so I should put triple the water through it? And when will know when it’s properly flushed mate
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Member of the Month: July 2015
Canna is good stuff are you following the Canna feed schedule? And using the other additives?

I assume you're using Canna Coco, if so there's nothing in that. But you mentioned a blend.

If you're running the Canna line, flush it, (twice the pot size worth of water) and hit it with some Rhizo, it's a very good bandaid.