HELP - leaves are curling and I don't know why....

[craftygirl]

2 of my plants in a large room (with several others that are fine) are having curling leaves, but I don't know why.

The set up:
10x10 room, grown in soil with perlite under T5HO 6400K lights (they are about 6 inches above the plants),
current nutrient levels are 5-5-12 and are getting nutrients every 2nd watering, so about once a week.
temp range is 70 (at night) to 82 (on a hot day) usually day time is around 78
Humidity ranges from 40-60%
lights are on18/6 schedule
Plants are 5 weeks old from seeds, and are Chocolate Haze Fem
there is a oscillating fan in the room, but it is farthest away from these 2.

They only started curling up like this about a week ago, and nothing I do seems to fix it. All the other plants in the room are fine, they are Super Lemon Haze Fem, Blueberry Fem, and 3 unknown CBD only (from a friend)

What could be causing this and how can I fix it?

I thought at first too hot, but this whole past week the hottest the room got was 77, and it's been way hotter than that before (84). I also thought not enough humidity, so made sure it was closer to 60-70-%, still no change. I don't think I'm over watering, as I wait until the soil feels dry about an inch down. I don't think I'm under watering as I give them just enough water so it starts to come out the bottom and puddle a little.

Please, any and all help is very much appreciated. Thanks.

[ellz]

Hello craftygirl. I am thinking it may be a root problem but exactly what problem is a bit of a mystery as it can be a number of things. My initial thought is the roots may be starting to overgrow the container. I can't really tell how large your pots are plus you say you have multiple plants and only these are doing it. If they are all in the same pots and about the same size, that wouldn't make any sense. If, however, these are in smaller containers, that might be it.

Another thought is feeding. How many plants are you growing and how do you do your watering? Do you just mix up a large batch and do them all or do you make up small batches for each one? Trying to determine if there is anything different about these. Maybe these are the last to get fed and the nutrient mixture isn't as strong or the pH is off? Kinda just spit-balling ideas at the moment.

One other possibility is that the trellis is causing them to curl when they touch and rub on it. If the problem started around the time they were about that high, that could be it. I have some new growth on my plants that look like that from touching the sides of my cabinet.

[tyler_ hobbyist]

I agree with the root problem, but different strains grow in different ways so this could be a strain that grows more roots and its root bound or root rot. The other thought is, do u have a sealed room with little air exchange? Because she could be sufficateing from either to much or 2little co2 as plants breath co2 like we breath oxygen. Under 200ppm of co2 plants start to sufficate and this could be a more sensitive strain than the others. But 1st I would start feeding b vitamins and transplant her into a bigger pot.

[Canyon Grower]

craftygirl , question, why are you feeding such high potassium right now? At this stage the normal would be something like 5-1-1. Im not saying too much potassium at this stage is bad, but then I dont know if its good either. High phosphorus and potassium should be saved for flowering.

[PRIMO]

HI Craftygirl , never having used t-5s I know nothing about em but maybe try rearranging your plants under them or raise the light some. Along with heat to much light intensity could also make em wanna taco shell for you. Just a guess though, good luck with them.

[D.A.A.S.69]

Morning CG Looks like she might have gotten a little too hot at some time. But it doesn't look to bad to me from the pics .Try placing you fans so they blow over the top of your plant. With just good air flow an not to powerful a wind. Good. Luck

[craftygirl]

Hello craftygirl. I am thinking it may be a root problem but exactly what problem is a bit of a mystery as it can be a number of things. My initial thought is the roots may be starting to overgrow the container. I can't really tell how large your pots are plus you say you have multiple plants and only these are doing it. If they are all in the same pots and about the same size, that wouldn't make any sense. If, however, these are in smaller containers, that might be it.

Another thought is feeding. How many plants are you growing and how do you do your watering? Do you just mix up a large batch and do them all or do you make up small batches for each one? Trying to determine if there is anything different about these. Maybe these are the last to get fed and the nutrient mixture isn't as strong or the pH is off? Kinda just spit-balling ideas at the moment.

One other possibility is that the trellis is causing them to curl when they touch and rub on it. If the problem started around the time they were about that high, that could be it. I have some new growth on my plants that look like that from touching the sides of my cabinet.

They are in a 10 gallon container, exactly like the rest of the plants in the room. I mix up nutrients in a large container and then fill a smaller easy to pour container and water them, usually starting at different ones each time.

[ellz]

Hmmm....that is odd then. The only other difference you mention is that these 2 plants are furthest from the fan so perhaps they are getting hot spots of temperature versus the others? I am not sure on that but I am still trying to see what would be different about the growing conditions among your plants. Maybe you could try adding another fan on that side? Just a though. Either way, I wish you the best with it.

[craftygirl]

Morning CG Looks like she might have gotten a little too hot at some time. But it doesn't look to bad to me from the pics .Try placing you fans so they blow over the top of your plant. With just good air flow an not to powerful a wind. Good. Luck

I've added a tower fan in front of them that blows on just them, so I'm hoping it'll start to go away soon.

[craftygirl]

HI Craftygirl , never having used t-5s I know nothing about em but maybe try rearranging your plants under them or raise the light some. Along with heat to much light intensity could also make em wanna taco shell for you. Just a guess though, good luck with them.

I had raised the lights for about a week and saw no improvement, so I put them back to the same height as all the others.

[craftygirl]

I agree with the root problem, but different strains grow in different ways so this could be a strain that grows more roots and its root bound or root rot. The other thought is, do u have a sealed room with little air exchange? Because she could be sufficateing from either to much or 2little co2 as plants breath co2 like we breath oxygen. Under 200ppm of co2 plants start to sufficate and this could be a more sensitive strain than the others. But 1st I would start feeding b vitamins and transplant her into a bigger pot.

how do you go about measuring ppm of CO2?

[D.A.A.S.69]

Co2 won't help unless you have maxed out your light, and you haven't. Give her a little while ,maybe she will improve. Good Luck

[tyler_ hobbyist]

U can buy co2 ppm meters or u can buy siringes with test tubes that messure ppm as well but I would sugest the meters there about 100bucks but way more usefull

[craftygirl]

craftygirl , question, why are you feeding such high potassium right now? At this stage the normal would be something like 5-1-1. Im not saying too much potassium at this stage is bad, but then I dont know if its good either. High phosphorus and potassium should be saved for flowering.

I was given these seeds from a grower friend and was told that's what they always use, so I did the same.

[tyler_ hobbyist]

Temp and light are the main factors with co2. In my exspereince 1000 watts per 5x5 space the plants only use about 800ppm anything more is a waste without more light, in a 5x5 space with 2 lights of 1000watts the plants then use closer to 1500ppm of co2. This is just my exsperince. By the way in the pic, canabbis is a c3 plant

[stevenics]

hey crafty girl, i didnt read all the responses so i dont know if anyone else mentioned this, the first thing you should do is check the runoff ph. this way you will know the ph of the soil, if you dont already check the ph before watering, try that for a little while to make sure you are watering with the correct ph. but the runoff ph will tell you if you have any ph probs in the soil. i mention this because it seems like you have a root problem, whether they are just to big for the containers they are in, or they are just not uptaking nutrients properly due to improper ph. whenever you have a leaf issue, like curling leaves or spots, always start with checking the ph. Good luck and happy growing!!

[stevenics]

your plants look great, i would not put lots of concern into that leaf curling, unless it gets significantly worse, i wouldnt worry to much about it. good luck with gettin this takin care of, and again your plants look awesome.