Tips of leaves curling under - is this heat stress?

I've searched all over this forum for answers to this, but I can't seem to come up with anything that seems like a perfect match. My girls seem to be doing fine, but a lot of their leaves are curling under at the tips. This is most common with much younger leaves, but some of the well-established ones show this as well.

Otherwise, they seem to be healthy. Is this heat-related stress?

This could be a bunch of things. Broad mites, strain (NL crosses like to do this), over feeding nitrogen, and maybe whatever you said that i didnt read i just looked at the pictures but most of the time you know your plants better than us so lol. Ya.

Its called clawing and its either a genetic trait or nitrogen-specific toxicity.

deadgro said:

Its called clawing and its either a genetic trait or nitrogen-specific toxicity.

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what he said, OR over watering. Not heat

Nitrogen toxicity.
Can tell from yellowing tips,
claw
dark green colour
deformed new growth

Heat and light stressed plants usually canoe and like fold into themselves like a taco. They look like theyre hiding from the sun in a way. Then the leaves droop when the moisture levels cant keep up with the heat. Then the branch tips follow and shortly after that the leaves start withering on the plant and die from the tips to the center eventually.
Whoever said theres burnt tips, can you show me where you see that? All i see for yellowing tips is the very point of one has the tiniest yellow tip on it. Nothing like omg look at that though. Id say its probably just the plants charecteristics but i might be inclined to back off on the food for a week just to be sure it isnt over feeding.

Thanks!! Much appreciated. I really love this forum!

Alienwidow said:

This could be a bunch of things. Broad mites, strain (NL crosses like to do this), over feeding nitrogen, and maybe whatever you said that i didnt read i just looked at the pictures but most of the time you know your plants better than us so lol. Ya.

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I fed them Fox Farms "Grow Bigger" - half of what was listed on the label, and it was STILL too much! Amazing how potent that stuff is. I bought a small bottle, and it looks like it will last forever.

I'd give them a good flush with pH'd water. If that fixes it, I'd say N toxicity.

what kind of PPM's are you feeding them?

TequilaGrower said:

I fed them Fox Farms "Grow Bigger" - half of what was listed on the label, and it was STILL too much! Amazing how potent that stuff is. I bought a small bottle, and it looks like it will last forever.

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Just remember a full dose is for a large mature plant under a 1000 watt light. Like three month veg or more large. And you probably already know that if your using fox farm ocean forest that you dont need to feed for the first two weeks at least and then you should just ease into feeding them. Ffof has a pile of nutrients thatll go a long way.

Im having the same problem look.There 3weeks old at first I think I feed to soon for seeds then I flush them last week today first feed with sensi.grow.I have them under 600watt.what is the problem?

I've been giving them RO water without any nutrients and they are looking super healthy and happy now. Whew. Thanks for the advice!

zilla2126 said:

Im having the same problem look.There 3weeks old at first I think I feed to soon for seeds then I flush them last week today first feed with sensi.grow.I have them under 600watt.what is the problem?

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I'm certainly no expert, but I can't get a good read on your plants because everything is too yellow. Maybe turn off the lights for a few seconds until you take the photo?

zilla2126 said:

Im having the same problem look.There 3weeks old at first I think I feed to soon for seeds then I flush them last week today first feed with sensi.grow.I have them under 600watt.what is the problem?

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With the light son all i could tell from that picture is there is like a slight chance they are overwatered? Hard to tell with all the yello