bubblegum & neem (and nycdiesel)

I use neem oil about once a week in veg and carry that into the first few weeks of flowering. It really does seem to help. I kill the HPS and apply, let dry with all the fans on, etc, then turn the lights back on a half hour later when all of the wetness is gone.

I grew some bubblegum last round, and the leaves just looked like shit from bottom to top. Well, I just moved one over from veg to flower and it had the same problem except for the new growth in the flower room, but I was behind on my neem and I now realize, looking at a couple plants, that the crappy brownish/yellow destroyed leaves are from the neem oil.

It also appears the NYC Diesel is having the same issue, though maybe less severe....

any tips on this? Is a half hour too short? I'm afraid to spray at night as the humidity will just linger in the room till morning.

as an aside, the bubblegum buds didn't suffer. Got a fantastic yield from a plant that had barely any leaves left! I just wonder what would have been if htis plant could have reached full potential.

the interesting thing is most of the strains DON'T have any problem with my method.

(buddha's sister, sk1, jacks cleaner 2, blueberry, grapefruit-x-?? are all unaffected)