We've hit 28 for two nights this month and my BOP have no damage. There are others around town blooming their heads off right now. So there must have been another factor- wind maybe?

Hmmm...

Wind and I think sudden sunlight, (due to deciduous trees shedding their leaves) might be a factor....My yard goes from very shady in the summer and fall to suddenly very sunny in the winter.

Thanks for the info. I can transplant it under the eaves of my house, where it is shady and warmer. It's good to know that it has done fine at 28.

pricklypear,
are we talking about the same BOP? s. reginea is the one that took 28 just fine. s. nicolai (giant/white BOP) goes unaffected in areas protected from wind, while the ones out in the open get their leaves burned (like bananas)