Advice on slight leaf curl?

A few of the full size leaves close to the top of the plant are starting to curl down slightly. The new growth above and the big leaves below don’t seem to be affected. The only thing I see being listed as a cause with otherwise healthy looking leaves is nitrogen toxicity. I don’t think my plant looks dark green like in the pictures of N toxicity I see online. None of my leaves have any discoloration or burned tips or brown spots.

I am wondering if this is happening because I am transitioning the height of my light from 24" to 18". It is currently at about 21". Plant is just starting to flower. GSC autoflower.

I am in FF Ocean Forest and no nutrients yet so Nitrogen issue doesn’t seem likely?

I wouldn’t worry about it.

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So no need to raise the light back up to 24"? Thanks.

Looks like possibly a slight heat/humidity issue. What are your temps and humidity? It’s nothing major so nothing to be concerned about.

What do you mean raise the light back up to 24"? What kind of environment and light are you using?

I stopped running my vaporizer so the humidity is currently at 47% and the temps are up to 77 during the day and around 69 to 70 at night. Before flowering I was keeping the humidity at a minimum of 55% and sometimes it would creep up to the upper 60% range with the same temperatures.

HLG 260W QB V2 rspec. I have been consistently keeping the light at 24" from the top of the plant. Now that she has started flowering I am letting the distance decrease until it comes down to 18". I’m growing in a closet that is a little smaller than 4x6.

All I was wondering is if the light being closer has started to affect the leaves even though there are no other signs of light burn.

I think she wants more humidity honestly. Try getting the RH up to 55-62% for a few days and then see how she looks.

This is my first grow and flowering snuck up on me so I was afraid of the humidity being too high at this point. Since most people are in agreement the plant doesn’t look bad enough to have any worries am I ok to let the humidity sit around 47% for now? I have a dehumidifier so when I really need the RH low I am able to get it down.

I calibrated my humidity gauge with a 75% boveda pack so I know it is accurate.

You don’t have to worry much about the humidity right now. 50% is fine. Towards the end cycle you will want to get it to around 30%. Too high humidity at the end can cause mold problems. But for now you’re fine. The leaf curl is most likely heat stress. Not a real big deal, but if you’re worried about it, I would raise the light a little.