Heat stress or deficiency??? Please help

J

jav2043

Member

• Jul 17, 2015

• #1

Getting a lot of pale green/yellowish leaves on top of canopy with some leaves drying out completely. This started once I flipped about 2nd week during stretch. At first I thought they where under feed and tried raising ec but still happening and getting worse. Any idea???

Growing in 5 gallon smart pots promix soil bx with ewc and 10% perlite. Room is sealed 600 watt hps bout 12-18 inches off canopy 1200 ppm co2 gas burner humidity 60%. Feeding hydroponic research HD formula with +size booster last feed 2.3ec normally 1.8 ph 6.3

Was gonna fill out infirmary form but missing a lot of information which I will get next feeding but trying to get it under control asap if possible. Any questions please ask much appreciate any advice.

Thanks
Joe

 

Last edited: Jul 17, 2015

J

jav2043

Member

• Jul 18, 2015

• #2

Anybody???

 

DoubleTripleOG

Chemdog & Kush Lover Extraordinaire

ICMag Donor

• Jul 18, 2015

• #3

What's the temperature getting up to during lights on? What's under the plants, do they sit in run-off? Is the flame on the co2 genny blue?(it should be)

I take it by your description that your using a co2 monitor/controller to run the genny? Have you calibrated it lately? If it's a C.A.P. controller you be better off to throw it out and run the genny on a timer.

Your EC seems a little high as well. I usually top out at 1.2. Most of the time, less is more. If none of those things I listed are the cause, I would guess some kind of pest attacking the roots. Is there any way you can get a look at the roots and see what they look like?

I'm no expert, just trying to help. As I had 3 or 4 CAP controllers shit the bed on me, one right after the other. If the genny isn't running enough, the plants will suffer. Like for instance if the controller says it's 1200 ppm, but really it's 100 ppm or less.(what happened in my room).

Roots sitting in runoff will mess them up, and can cause the yellowing your experiencing. Lot's of different variables come into play in a sealed room. I would troubleshoot each variable if I was you, until I found the culprit.

Oh, and by the way, how are you cooling the room? You expressed that heat may be the cause. Portable AC? Window banger?

 

J

jav2043

Member

• Jul 20, 2015

• #4

Thanks for stopping in DTOG. The temps stay around 83-85 with co2 at 1200 ppm controlled by autopilot master controller. I hear you on the CAP equipment as I had to toss one out myself. Luckily I did a search and learned to stay away from them before buying another CAP. Using a 4 burner gas generator and did check recently all blue flames. I used a smaller portable co2 monitor to check if I needed calibration and it was only off by 15-20 ppms so I left as is. I'm cooling the room with 24k mini split and 2 70 pint dehumidifier soft humidity. Plants are sitting on 4x4 trays I built pitched to catch run off on gutters.

Are you running 1.2 in soil or coco? I was at 1.2 during veg and they blew up but once I switched they started to look hungry and after some research read soil likes to be higher especially during peek stages of flowering. Can't believe everything you read but seen some say 2.4-2.6 ec. Could be wrong but I don't see any signs of burn.

I just picked up some yellow sticky traps as I saw what look like a fungus gnat. Don't have an infestation to affect the whole room but something I will take control of before its to late. Tomorrow I have to feed but will be taking some samples to see if my ph is off in promix. Trying to troubleshoot all possibilities cause this has stressed. Will take a closer look at my roots make sure it's not pest issue. Thanks again for tips. Feel free if you could think of anything else or any questions. I hope I could save this run and yields won't be affected as bad.

 

RonSmooth

Member

Veteran

• Jul 21, 2015

• #5

The canopy looks hot. The plant folds its leaves to minimize surface area when radiant heat is excessive. Your room temps might be 85 but the surface of the leaves directly under the light is probably 20 deg hotter. Think blacktop on a sunny day.

12-18" is too close. I keep my 600 at least 24" and run an 18" fan so there is plenty of air movement in the area directly under the lamp. I still get it but it doesn't seem to affect flower development or yield.

The one dead leaf in your pictures appears to be unrelated. I wouldn't worry.

 

4

420peezy

New member

• Jul 21, 2015

• #6

This is not heat stress, you have broad or russet mites, get a 100x scope and check it out. Youll need a product that targets Cyclamen mites, which are soft shelled mites that include broad and russet. Act fast or your buds will disintegrate in front of your eyes.

 

J

jav2043

Member

• Jul 21, 2015

• #7

I did some ph testing today and it was off. Used RO water 6.5 ph going in and coming out at 5.9 ph. That's a pretty big swing so I feed at 7.0 ph see how that works. I also checked runoff ec on two different plants and the plant that still looks healthy run off was 3.8 ec and the ones not looking so great run off was 2.5 ec.

Ronsmooth I was considering light intensity or leaching. I have good air flow with 8 oscillating fans in a 12x16 but running 8 600 watts might be causing some bleaching. Considering using 6 next run one per 4x4 cart see if that makes a difference.

420peezy did check today for any signs of pest and didn't find anything but since desperate to save this run gonna top dress with some diatomaceous earth.

Thanks guys for stopping in.

 

Avinash.miles

Caregiver Extraordinaire

Moderator

ICMag Donor

Veteran

• Jul 21, 2015

• #8

does NOT look like Hemp Russet Mites or Broad mites at all to me (i've had the hrm's).

yellowing from the top down usually says "iron deficiency" to me.

 

P

puff adder

Member

• Jul 21, 2015

• #9

OUCH!

In all my 30 years of growing I've never gotten broad mites. I've read about them and dreaded the day I got them.

I'll loook at things under a microscope and see.

I've read that Avid kills the effectively, is this true?

 

shredGnar

Member

• Jul 21, 2015

• #10

I'm willing to bet it is your gas burner... Looks just my plants when I was having this issue.

There is likely not enough O2 in the room for the flames. When there is a lack of oxygen the flames produce ethylene, not harmful to humans but detrimental to plants.

https://www.icmag.com/ic/showthread.php?t=236262&page=38

Look at posts 569 and 570...

 

br26

Active member

• Jul 21, 2015

• #11

classic heat stress.... light baking them. back off light or fix the vent issue so it pulls the heat better

 

J

jav2043

Member

• Jul 22, 2015

• #12

shredGnar said:

I'm willing to bet it is your gas burner... Looks just my plants when I was having this issue.

There is likely not enough O2 in the room for the flames. When there is a lack of oxygen the flames produce ethylene, not harmful to humans but detrimental to plants.

https://www.icmag.com/ic/showthread.php?t=236262&page=38

Look at posts 569 and 570...

Click to expand...

I have read something about this but what has me confused is I vegged for 6-8 weeks and no problems. everything is green and lush to the point where I flip my lights. Once I go 12/12 during stretch I begin to see leaves start turning. When did you begin to see effects of ethylene? I did read up on this somewhere on here but i checked my flames and saw them burning blue so I ruled it out. Now I'm reconsidering switching to bottles and see if comes under control.

Avinash.miles said:

does NOT look like Hemp Russet Mites or Broad mites at all to me (i've had the hrm's).

yellowing from the top down usually says "iron deficiency" to me.

Click to expand...

Just did a quick research and could be a possibility. Will look into this as well make sure I cover all my bases. Thanks for all responses guys.

 

shredGnar

Member

• Jul 22, 2015

• #13

2-3 weeks in flower the plants would go to shit.. heavy yellowing and neurosis. I have a separate veg room with no burner and had never had problems in veg.. Do you run the burner during veg as well? At the same ppm??

I am growing at altitude, and had the high altitude jets installed, the flame burned blue with no visible yellow. Perfect blue star...

I never did a test for ethylene so I can't say for 100% certain that it was the problem, but after I switched to bottled co2 I was rockin and rollin.

 

shredGnar

Member

• Jul 22, 2015

• #14

This picture looks exactly like what I would deal with. They eventually start drying or falling off the plant. Would look like October in the woods during the harvey, dead leaves everywhere.

 

J

jav2043

Member

• Jul 23, 2015

• #15

shredGnar said:

2-3 weeks in flower the plants would go to shit.. heavy yellowing and neurosis. I have a separate veg room with no burner and had never had problems in veg.. Do you run the burner during veg as well? At the same ppm??

I am growing at altitude, and had the high altitude jets installed, the flame burned blue with no visible yellow. Perfect blue star...

I never did a test for ethylene so I can't say for 100% certain that it was the problem, but after I switched to bottled co2 I was rockin and rollin.

Click to expand...

That's the same timing with mines 2-3 week in flowering. I start veg in different room but also veg for about 4 weeks to fill double trellis in same room at 800ppm weeks 1-2 and 1000ppm weeks 3-4. Turn up to 1200ppm at flip. LOL when I first saw picture was like oh hell yes that looks like same exact problems I'm having before I realized it is my problem. I switched to bottle today hopefully this will stop. The damage on leaves is already done but hopefully I could still salvage this run.