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We spend too much time chasing ambient RH percentages when the real late-stage killer is the Leaf Surface Temperature (LST) crash right after lights off. That sharp thermal drop drives the boundary layer below the locali...
We spend too much time chasing ambient RH percentages when the real late-stage killer is the Leaf Surface Temperature (LST) crash right after lights off. That sharp thermal drop drives the boundary layer below the localized dew point margin, and that's when condensation feeds botrytis. My solution is targeted thermal inertia: low-wattage substrate mats running only for 90 minutes preceding and following the dark cycle transition. It’s not air heating—it's stabilizing the slab to prevent the critical LST crash. But here is the hard question: Does that slight, sustained root zone heat during the dark period impact essential microbial activity or root respiration rates enough to outweigh the massive mold prevention benefit? We're trading one thermodynamic variable for another.
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