Hi
I think you'll be okay. obviously some types are more sensitive but on average they can tolerate down to freeze.
Generally they go dormant below 45 but it must be consistant. If the days are warm they will continue to grow. and flower. What is your plan for next winter??
Good luck!!! gary

That makes me feel better. Tonight is the last cold night but it's going to be up in the mid 70s today and then mid-80s the rest of the week. So far they are looking okay and the submerged pads still look like they are making their way to the surface.

This winter I'm either going to try to overwinter the tubers like I've read of some people doing or cut the larger pads back and bring the pots inside in a small plastic kiddy-pool and put it in front of the window in an extra room.

Years back when I tried this the first time, I tried overwintering tropical tubers wrapped up in lightly moist paper towels in baggies in the crisper drawer of the fridge (had read that online). It didn't work and I lost them all. I've since read some other methods that might work better.

Thanks again for the encouragement Gary.

But if they went dormant after being planted and submerged......wouldn't they just come out of it when it warmed up?

I honestly don't know. There isn't a lot of info out there about it that I can find. One site seemed to suggest that they wouldn't bloom that year or that it would set them back.

But, I noticed more pads on the surface today and last night was the last cold night. I think the crisis has been averted.

Hi
What is the reason you picked trops over temps?? I grow only tropicals because of the long ,hot summers in my area.
Particularly fond of "blue Goddess" because of the sky blue color and "King of Siam" due to the dark almost black ,purple color. Have never grown the temps as the two mentioned overgrow my small ponds anyway.lol
In zone 8 I'd think you'd be able to keep them in your pond over winter as long as the water doesn't freeze.
Mine have survived down to 27 for short periods. They sailed through the last two record setting winters but they did completely disappear during Jan.
Anyway hope your plants recover !!! gary

I picked tropicals because I'd already grown several varieties of hardies and was looking to get into something different, color and pad-wise.

I'm not sure about them overwintering in the pond, but I'm going to try several different overwintering experiments with them to give me a better chance of them coming back next year.

I did think about getting a stock tank heater and putting it in the lower pond to see if I could overwinter that way. I'm also going to collect the corms and try overwintering that way. Hopefully I'll come across a method that works that I can use year after year.