Can anyone identify this problem? (photos)

[AlterNation]

Soil is Roots Aurora (I used Ocean Forest for a while, but I swear it had bugs in it) and nutes are Roots Organics 7, except for the bloom, which is Pura Vida, and the ancient amber, which is Ful-power. Strain is a mystery Sativa.

Anyway, I have 3 different phenos of the same strain in their 5th week of veg. They were recently cropped down to level up with the bushiest one, but they're too big for the T5 now, so they just got moved under the 1K, which is on them 24 hours a day. I like to run the lights 24/7 for a week after I switch from T5 to HPS. The room is a bit warm (81-83) and dry (33%), but I don't have a tremendous amount of control over the environment, unfortunately. I can't afford an AC, and the temp will come down after the flip, anyway. I don't want to vary from my routine, but...I'm not afraid to admit when I need help.

They're yellowing from the top down. The veins are staying green. The leaf tips are curling. They're not burned at all, but this happened the last time I grew this strain and the plants ended up getting very stressed out and yellowing early and producing a bunch of fartdust which really threw off my fuckin' mojo. I need these ladies to do better this time. There's only 3 of them. Can anyone help me identify and correct whatever is lighting their tampons on fire?

Thanks!

Note: In the soil I've been running nothing but water for 10 days, but I DID accidentally fertilize them twice in the same week a couple weeks ago. They got a light foliar with humic acid 2 days ago.

 

[paulycali]

Did you just transplant? Move them to another room? They look like they are in shock. Also whats your water and air temps

 

[AlterNation]

They were recently cropped down to level up with the bushiest one, but they're too big for the T5 now, so they just got moved under the 1K, which is on them 24 hours a day. I like to run the lights 24/7 for a week after I switch from T5 to HPS. The room is a bit warm (81-83) and dry (33%), but I don't have a tremendous amount of control over the environment, unfortunately.

 

[thunderfudge]

33% is too low.espescially if veg was humid.do leaves look dingy?

 

[AlterNation]

veg was the same. My basement is very dry. I just spray them every few days. Please define dingy...

 

[Mississip Hip]

looks like overwater and heat stress to me. 70% RH in veg is a game changer.

 

[Classic Remix]

How far is that 1k from the tops??
You just put em under there?
What is your source of fresh air

What's nute regimen are you using

 

[woodsmaneh]

Looks like lock out caused by Ph and heat stress. Check Ph and water with 50% strength nutrients and hit them with some Cal-mag and they will bounce back. Move the light away and and give them 6 hours of dark to recover. When you move from T5's to 1000w make sure you have the light way high to start and over a week lower it back down, this avoids shock and stress, kind of like being in a dark bar and walking out into the sun after a few hours, hard on the eyes.

Weed is a c3 plant and does not require night during veg but I have had better results by letting them rest. I think you will also.

 

[vaporedout]

whats your ph at?

 

[Seamaiden]

I agree that pH may be playing a role here. The leaves look like they want some Mg, so if I were in your position I would hit them with a foliar of MgSO4 (Epsom salt) at the rate of 1/4tsp/gal water (include a surfactant, a few drops of liquid dish soap works fine here). If they green up, then you know what's up and need to increase Mg.

However, the warm dry conditions are going to make nutrient utilization much more difficult. Is there no way you can increase RH in there at all?

The growth at the top doesn't look yellow to me, it looks like they had a huge burst of new growth and are wanting for a wee bit extra N for that growth. I would follow woodsmaneh's advice about the lighting, I'm in agreement regarding the role of the changeover from T5's to 1000W HID lighting.

I would figure out a way to increase RH, too. A towel hung so that it touches a container of water is one good way to get some evaporative action going. Any container with water that has a sufficiently large surface area is going to give off water through evaporation.

 

[We Solidarity]

sounds like you just did too much at once and freaked out the plant - firstly moving from a t5 to a 1000 watt bulb that's on 24/7. That's almost a 10x increase in the amount of light the plant is getting. If your humidity is too low in relation to your air temerature, the stomata will close and your plant will drastically slow down it's photosynthetic processes. So there's a good chance you're dealing with light toxicity from having an extremely imbalanced vapor pressure.

I would never leave lights on a plant for 24 hours unless it was very small - especially if it's going into flower. Every time I have plants going from 24 hours of light to 12/12 it takes over a week for flowers to show. By comparison, letting them get sleep allows for fuller hormone conversion leading to healthier growth, less light-based stress, and faster flower onset.

I would get a humidifier over your canopy and set it on an interval timer until you can maintain a 10% increase in your overall RH, as well as cut your light cycle to 18/6. I'm pretty sure your symptoms are all environment based so DEFINITELY fix that before you start spraying anything on your plant. Also make sure you're not overwatering - when plants get light/heat/humidity stresses they can completely stop drinking and that can start swinging your PH if you don't catch it and water the pot.

 

[AlterNation]

Hey thanks for all the advice.

I agree. I done fucked 'em up on this run by trying to do too much. I've never had quite the same problem before, but I have experienced similar issues in the same way, when I've lost focus or pushed too hard. Too much pruning, too much light, too much water, whatever it is. I have had some lockout issues with this strain, as well, in the past and the last crop didn't really like the switch from T5 to HPS, either. I think it was a combo of all of the above (PH/RH/Etc.) and I didn't feel like dealing with it, so I decided to cull this batch, as it was the final run in this setup anyway.

Solidarity: That was an extremely informative and spot-on assessment. I reached the same conclusions. The only reason I kept them under 24 hour light this time is that they got too big for the T5 and I was trying to keep them in veg, as I was going to have to move them to a new location to flower, and I didn't want to try to move them post-flip. I would normally never do that. So, I took some cuts and shut out the lights on the moms. It's for the best, really. Moving on to bigger and better things, with some new-to-me methods and the help of these forums.

 

[We Solidarity]

Hey thanks for all the advice.

I agree. I done fucked 'em up on this run by trying to do too much. I've never had quite the same problem before, but I have experienced similar issues in the same way, when I've lost focus or pushed too hard. Too much pruning, too much light, too much water, whatever it is. I have had some lockout issues with this strain, as well, in the past and the last crop didn't really like the switch from T5 to HPS, either. I think it was a combo of all of the above (PH/RH/Etc.) and I didn't feel like dealing with it, so I decided to cull this batch, as it was the final run in this setup anyway.

Solidarity: That was an extremely informative and spot-on assessment. I reached the same conclusions. The only reason I kept them under 24 hour light this time is that they got too big for the T5 and I was trying to keep them in veg, as I was going to have to move them to a new location to flower, and I didn't want to try to move them post-flip. I would normally never do that. So, I took some cuts and shut out the lights on the moms. It's for the best, really. Moving on to bigger and better things, with some new-to-me methods and the help of these forums.

Yep - as long as you're learning from mistakes and gauging your techniques carefully you'll always be doing it right. The people on these forums are such an incredible resource, it's the whole reason I signed up. Good luck with the cuts and the new setup!