Late flower humidity targets before harvest, PNW perspective

If you're pushing into week 6-8 of flower out here in the northwest, your biggest threat isn't bugs or deficiencies anymore. It's the wet air rolling in off the coast every night. Botrytis doesn't ask permission and dense colas in cool damp conditions are basically an invitation. The number I chase hard is 45-50% RH during the day and I want it no higher than 55% at night. Once you're consistently seeing 60%+ overnight in late September, you're gambling. A lot of people learn that the hard way their first season running something with tight bud structure. Temperature swing matters too. Big swings between day and night temps cause condensation right on the buds, especially inside the canopy where airflow is poor. I try to keep my day-to-night swing under 15 degrees Fahrenheit if i can manage it. Trellising and defoliating for airflow through the interior is something I do around week 4-5 specifically to set up for this problem. Anyways, if you're seeing any discoloration in the calyxes or a slightly off smell in specific zones of a cola, pull those sections immediately and check underneath. Botrytis spreads faster than most people expect. The harvest timing I'd give for a mold-susceptible strain in wet weather is simple: harvest a week early before you harvest nothing at all.

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Seedling2d ago

Solid Information can confirm. Harvest a week early before you harvest nothing at all. Dense buds can absorb a lot of water, especially in the early morning hours.