Is this more likely Heat Stress or Mg Def or ?
All 4 of the widows I have are showing the folded curled up leaves. The pictures show just one plant.
Nirvana White Widow - 18 days in veg.
FFOF 1.5gal container.
76-78F / 45% RH .
No nutes - gave one feeding of 5ml cal-mag
PH water is around...