Leaves curling up. Why?

[NateDog]

Hello everyone.

This is my first grow.
I'm growing in Foxfarm mixed with 35%
I have ten different strains but in only having issues with amnesia auto and critical cheese auto some of the other strains are showing a tiny but of curl on 1 or 2 leaves but not much.
I water when the top 2 inchs are dry I check with a meter, also use the life method for good measure lol.
Today is day 1 of week three
No bugs. I've been checking everyday.
Yellowing on leave but we figured out we were accidentally getting the leaf on the amnesia wet when spraying the clones. So far no more issues with that.
1000w hps light is 3' away from my plants
I have ladybugs to prevent pests.
Temp stay between 74-82 mostly around 78
Rh is normally 60% but sometimes falls down to 55%
I have a fan blowing accross the plants.
I fed 1/4 strength nutes last week and I watered them yesterday. I'm using Foxfarm nute trio. I only fed big bloom and it seemed to make the problem a little better until 2 days ago right before I watered with plain 0TDS WATER
I Ph my water to 6.5 with ph up and down

At first i thought it was just the amnesia auto strain because the rest of the plants were fine but im beginning to see more of this here and there on some of the other plants. I'm thinking they just need more nutes now.

Pics:

 

[Spimp]

Here my opinion. Take it for what its worth sir.
This is a classic example of "margin rolling". They most common reasons for margin rolling are too hot, too humid/too much water,too much light.
MJ uses the roll to increase transpiration mostly. Exhausting water and minimizing photo areas .

Your specs on the grow room seem to be correct. Id take another look to see ifshe is getting too hot ormake sure the fan is making the leaves "shimmer". Too much direct light blasting them can cause them to say enough already and roll up.
Hope this helps in some way sir.

 

[NateDog]

I'm definitely guess too much light. I forgot to add I leave lights on 24/0 should I change them to less time?

 

[Spimp]

Yes. Try 18-6 for one or two days and Id bet money that was the culprit. do you ave a dimmable ballast? That may work too.

My opinion is that MJ can only use so much light until it has to focus her energies into making more food to keep up.

 

[NateDog]

Okay I will try tonight unfortunately I'm going to have to wake up in the middle of the night to turn the light back on.
Ill post how it goes.

What kind of timer should I buy?
Will changing the light cycle affect the plants in any way?
I want to try to do 20/4.
I'm trying to reduce the height as much as possible.
I read that the 24/0 increases yields slightly and makes the plants a little shorter.
Thank you!

 

[Spimp]

Okay I will try tonight unfortunately I'm going to have to wake up in the middle of the night to turn the light back on.
Ill post how it goes.

What kind of timer should I buy?
Will changing the light cycle affect the plants in any way?
I want to try to do 20/4.
I'm trying to reduce the height as much as possible.
I read that the 24/0 increases yields slightly and makes the plants a little shorter.
Thank you!

I dont have a timer personally. My runs are more micro ghetto style sir. I cant reccomend one, but several growers just use ones from bLowes or home Sleepo.
Making one or two light changings is fine. Multiple light stresses can cause hermies but this is almost always light leaks during dark period.

Heres my opinion on the 24/0 schedule = smaller plants and bigger yields:
Its smoke and mirrors.

MJ plants have only 100% "energy" at any given time. During light hours this energy is dividing into many things but Ill use 3 as a basic example-- Photosynthesis, Rooting, Growing. Lets assume it avg's to 33% energy for each.
Take away light and you have 33% energy left over that can go into Rooting and Growing. So now you have 50% on each. More "action" if you will.

So when you change to 12-12 for flower, you notice a growth explosion because now rooting and growing are crazy amplified vs what she did under 24/0. So when the short fat plants finally gets the rest, she explodes.

Alot of growers may disagree with my opinions on this but thats what opinions are for. And your welcome sir.

 

[Jimmycricket]

Just buy a timer for 4 dollars you cheapos lol.

Get a regular ol analog timer from hardware store.

As for whats wrong with the leaves, it looks to me like its too hot. You say temps are 65, but the plant looks like it gets much hotter.

 

[donpaul.p]

spimp and jimmy are spot on, the problem is heat stress, the leaves are cupping up as their trying to lose moisture quicker to cool down,

so raise the lights or use fans to lower the temps and your problem will go away,

also get a cheap timer they cost next to nothing, you dont need digital timers, these plants also benefit from a dark period over 24 hours so go with something like 18-6 or up to maybe 20-4, 24-0 tends to cause problems and ive found that plants grow much better when they get some dark period,

what you can do is set the timer so the lights are off during the hottest part of the day, make sure their are no light leaks and set timer to switch off when its the hottest time of day, pick one time schedule and stick with it, but reducing from 24-0 wont cause any problems but i would give it at least 4 hours dark period per day,

at night the plants use the energy they have stored during the day time hours to repair any damage done such as leaf loss or any type of stress, at night plants also use their stored energy to grow roots, more roots means a healthier plant, also when the lights are off the plant is still growing, it sort of stretches to find the light again, this is why the plants stretch when we go 12-12 they are trying to find the light again just like a plant thats in the shade, so a night period will benefit the plant and will help with the problem your having,
when you run the lights 24-0 the plant still does this process but by the light been on your just paying more for electric as the plant still has some down time when the leaves will look droopy, so id pick a new schedule and stick with it till flower

cupping is clear signs of temps to high.

i also see some brown rust like patches on the lower leaves, would need a closer pic to see for sure but it looks to me like you have some kind of nutrient problem, possibly to much nutrients,

what are you feeding them and how often, is it every feed or every other feed that you give nutrients, the leaves look a dark green so this could be a sign of to much N at this stage of growth.

so lets get the temp issue sorted first, you should notice a difference within a couple of days once the temps are down to where they need to be, im not sure if i can see the ends of the leaves curling down but this could be a sign of to much N but lets see how they look after the temp has been sorted

 

[NateDog]

So it was definitely heat you're right! I turned the a/c back there up a little and viola! The leaves are flattening back out! As for the color of the lower leaves the wife was accidentally spraying water on them when she was spraying the clones. Everything is going fine now so I will leave the lights on 24/0 and see how it goes. Hopefully this will make them a little shorter. I'm going to have to get supplemental lighting soon I may run out of space. The amnesia auto are showing buds already! I did 1/4 strength nutes 2 weeks ago and I'm planning on putting in 1/2 strength big bloom 1/4 grow big and 1 tblsp Blackstrap molasses per gallon next watering.

 

[donpaul.p]

cool, glad you got it sorted, just keep an eye on them bottom leaves, hopefully its down to the spraying,