My leaves just started to look like this. I did move the light closer and I used a lux meter to make sure they weren’t technically too close but maybe the light IS too close?
I’m thinking the light looks too close but you might want to fill out a support ticket…
COPY/PASTE: This “Support Ticket” into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA
Strain; Type, Bag seed, or NA
Soil in pots, Hydroponic, or Coco?
PH of runoff or solution in reservoir?
What is strength of nutrient mix? EC, or TDS
Indoor or Outdoor
Light system, size?
Temps; Day, Night
Humidity; Day, Night
Ventilation system; Yes, No, Size
AC, Humidifier, De-humidifier,
Co2; Yes, No
Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you
they are sweating is simplest way to put it not a bad thing so long as you aren’t feeding heavy since they are sucking moisture from soil and much like a dog panting. This is open stoma and transpiration
Like I said not nessicarily a bad thing move your temp gauge higher closer to canopy I am betting somewhere around 78f the leaves curl up to reduce surface exposed to heat of light
Strain; S.A.G.E. and (2) Bubbledawg Chicle
Coco/Perlite: 5 gallon Smart Pots
PH of runoff: 5.8
What is strength of nutrient mix? 425ppm
Light system, size? 400w MH, 600w HPS
Temps; Day: 75F Night: 65F
Humidity; Day: 55% Night: 55%
Ventilation system; No; Sealed garden. Fan cooled hood.
Humidifier: Yes; on automatic atmosphere controller
De-humidifier: Yes; CFM fans on automatic atmosphere controller.
Co2; Yes, 4 garden pads.
Thanks for the response! The Coco still feels damp, but should I give more water? It’s been 5 days since I have but usually wait for 7 days between Watering.
What is the PH you are putting in?
nevermind, I missed the coco part.
Answer: Heat stress.
This looks like the result of excessive heat. When the the serrated edges of marijuana leaves curl like that, it’s often a sign of heat stress from too high temperatures or hot spots.
When the problem is low humidity, the leaf will tend to fold in the middle,
What’s your temperature in your grow area? Is there a hot spot around these plants from the grow light?
If your light is simply too close, you can move the bulb further away from these plants and this issue may resolve itself. However, these leaves are showing symptoms of heat stress, without light stress (burning / spotting), so it’s more likely that the light is a good distance away and the heat just isn’t being controlled properly.
When growing with hot HID lights, you’ll need good ventillation and an exhaust fan will go a long way. If the whole grow area is too hot, you will want to consider venting out all that extra heat.
Having good air movement, like a small fan in your grow tent blowing over the tops of your plants, can help prevent hot spots from forming directly under your grow lights.In general, if it’s too hot for you to be comfortable, it’s too hot for your plants
Thanks for the response. Maybe the glass of the hood is too hot for them because the tent stays in the 70s when the light is on but it is much closer than I had it to the plants before I bought the lux meter.
Put your hand on top of your plants each of them and see if you can feel heat. if its to hot or uncomfortable for you them it is for your plants,
I have the same setup you have only i run a 1000 watt HPS
Good idea. Thanks for your help!
considering that even lower leaves are showing same response I wouldn’t jump to heat stress so fast @Paranorman has a nice little thread going on the cult of waving girls? He may have some input for this topic as well?
I know I had my ladies in mid 80’s with little signs of heat stress and though you are measuring temps from bottom of tent with co2 they will handle temps in the 80’s no prob. A vented and cooled light you can get them pretty close before heat is a factor also, do test with back of your hand though
To me they look healthy and comfortable nice colour perky lots of airflow you are doing everything right
Looks like heat stress to me, my Cultic girls-who-wave don’t wave like that, they lift their leaves up, like praying to Jah…!
I believe those leaves are canoeing from heat stress like Will said above…!?
Edit: …here’s a picture of me heat stressing my girls ( not on purpose ! )