I left my mandevilla outside this winter and it froze. I had to cut all of its beautiful vines. Do the roots die too? I reported them a few weeks ago, but it doesn't look like anything is happening yet. Does it just take awhile? Also, I let my bougainvillea freeze too. It was also repotted, but is just a branch sticking up out of the pot. It doesn't look like it's doing anything either. Any advice?
It's survival depends on how far below freezing (32 deg) the temp dropped, how long the freeze lasted, the age of the plants and If it rained during that time and the water in the pots froze then you can probably start looking for replacements. And since both those plants are known to be very cold sensitive you might have to replace them.