This looks like light burn? Anyone agree

It looks a little like mine and I know mine is light burn. Some of the rust looks pretty far down into the plant and that makes me wonder. Has this been going on for a long time?

I'll go with a nutrient issue because the symptoms the plant is displaying are those of a nutrient issue.

One reason is that it doesn't follow the pattern of light burn. Leaves at many levels of the canopy have the same symptoms. Light burn will impact the leaves that are closest to the light source and the damage will decrease as you move lower on the plant. That's not what we're seeing.

Also, you don't have desiccated plant tissue (plant touching an LED) or charred tissue (HPS). The discoloration and necrosis patterns are patterns of a nute imbalance.

Finally, excess light can destroy leaf tissue if you really work at it but the further you go from the light source, the physical damage will recede and the symptom will be those of light avoidance - tacoing/canoeing and "praying" and rotation of the leaf around its petiole (the same way we close Venetian blinds to control light).

If your ferts have been properly mixed and applied, I'd look at VPD. VPD controls water flow. Inadequate water flow causes all sorts of hell for plants.

Feed stronger (at least on one plant) and see how it goes. You might be surprised at how much light they can take when they are properly fed. Good luck.

Triplefastaction said:

Feed stronger (at least on one plant) and see how it goes. You might be surprised at how much light they can take when they are properly fed. Good luck.

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The pale leaves make me thing low N or an imbalance but the pattern of discoloration looks like an imbalance, no?

Lacking environmental data, it's going to be "try this, try that". That's not troubleshooting, that's recon by fire.

Ok so yeah I hear that about the damage on the lower leaves being like that at the top so that a good indication that its not the lights.

I have just thought something, a couple of weeks I was told multiple times I had fed them too much N and yeah the plants had dark leaves and was pointing to that and I looked at the canna A and B dosage and I was feeding the same amount of both in my daily watering, this problem started easily 7 days ago and 5ish days before that I left canna A bottle out and have used just the B bottle as the A has all the N...its obviously the reason for this..

Tomorrow (Monday) I'm going to water with both A and B.. should I use the same amount of both or slightly less A?

Thabks for the replys

CraigMk said:

Ok so yeah I hear that about the damage on the lower leaves being like that at the top so that a good indication that its not the lights.

I have just thought something, a couple of weeks I was told multiple times I had fed them too much N and yeah the plants had dark leaves and was pointing to that and I looked at the canna A and B dosage and I was feeding the same amount of both in my daily watering, this problem started easily 7 days ago and 5ish days before that I left canna A bottle out and have used just the B bottle as the A has all the N...its obviously the reason for this..

Tomorrow (Monday) I'm going to water with both A and B.. should I use the same amount of both or slightly less A?

Thabks for the replys

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Ouch. Mixing up the ferts - I suspect we've all had that "oh no" moment.

If you're in soil, what I've picked up from reading about soil grows is that you would flush with three times the amount of water but check with someone who does soil to be sure. If you're in hydro, just swap the res.

Insofar as what to feed them next, you really should nail down the actual deficiency. Those colors and patterns look like Ca or Mg to me but I don't know much about fixing imbalances so, if that's actually the case, it was just a good guess.

A key point is that > N might have caused a lockout so the fix might not be the obvious one.

Heh, what about contacting tech support for the nute company? It's their ferts, let them earn their $$.

Delps8 said:

One reason is that it doesn't follow the pattern of light burn. Leaves at many levels of the canopy have the same symptoms. Light burn will impact the leaves that are closest to the light source and the damage will decrease as you move lower on the plant. That's not what we're seeing.

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That's what I was tring to say. You wold had to be burning them for weeks to have that much browm throughout the plant. The very top leaves are the ones to expect light burn.