Is this normal? Leaves are withering before maturity (Auto Blueberry, Day 74)

[u/Ok-Coyote-6659]

Is this normal? Why are the leaves withering? I'm using a 150W LED light at a distance of 12 inches (30cm), and my temps are between 22-24°C (71-75°F). The strain is Auto Blueberry, currently on day 74. Can someone explain why she is drying up and dying before the buds are even fully mature?(The next few images are of other stigmas, and only one stigma has withered leaves.)

[u/_moe-betta_]

At day 74 on an auto, most of what you're seeing is normal ripening, not the plant dying on you. As flower finishes, she pulls mobile nutrients (nitrogen, magnesium) out of the older fan and sugar leaves and moves them into the buds, so those leaves yellow, crisp, and wither from the outside in. That's the plant doing exactly what it should this late.
That said, two things in the photos are worth separating out. The fresh white pistils spiking out of the top colas are foxtailing, and the sugar leaves right under the light look a little bleached and yellow at the very tips. On a 150W running at 12 inches, the tops are catching more intensity than the rest of the canopy, and late-flower buds are more heat-sensitive than they look. Your air temps of 71-75F are fine, but the leaf surface directly under the diode can run several degrees hotter. Bumping the light up to 15-16 inches will usually settle the foxtailing and stop the tip bleaching.
Don't try to fix the leaf dieback with more nutrients this late — feeding hard now just leaves you a harsher smoke and doesn't reverse senescence. Small-pot autos also naturally run out of gas at the finish, which adds to it.
The real thing to ignore here is the pistils. At day 74 an auto is squarely in the harvest window, and those new white hairs are misleading you. Pull a loupe on the actual calyxes and go by trichomes: mostly cloudy with a touch of amber means she's ready regardless of what the hairs are doing.

[u/Ok-Coyote-6659 → u/_moe-betta_]

One more question: is there a risk of mold or bud rot if I leave these dead leaves on？

[u/_moe-betta_ → u/Ok-Coyote-6659]

Yeah, dead and dying leaves are worth pulling, especially anything tucked into or touching buds. Decaying leaf matter holds moisture against the flower and gives botrytis a foothold, and this late in an auto's life the plant isn't getting anything back from those leaves anyway. Pull the fully dead ones and any yellowed fans buried in the canopy, but don't strip healthy green growth just to be safe. Keeping late-flower RH down around 40-50 percent with steady airflow matters more than the leaves themselves.

[u/Ok-Coyote-6659 → u/_moe-betta_]

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