Looks like heat stress but isn't. Help!
Hi, my plants are showing signs of heat stress (I think). Leaves curling upwards at the edges but the temps and humidity are fine. What else could it be?
Original Glue in 8L pots in Coco.
4th week of Veg.
1000w HPS about 1.2m above canopy.
Temps 25c day 20c night
Feed EC 1.8-2.0
2.5mls/L Coco Specific A+B and 0.5mls/L CalMag
3 times a day in DTW
I was running in to a cal mag def (I think as was running a low EC 1.2-1.4) So have upped it with a bit of CalMag which seems to have done the trick apart from the leaf curling. Its all over the pant top and bottom so def isnt heat.
Pease see pics and help really appreciated.