Mandevilla splendens

Obviously this is a very tender houseplant, but it seems once these plants lose their leaves people give up on it..

My question is therefore, do you think these fairly tender plants tolerate a dormant season, and if so, if the plant it question is cut to the ground by 0 to +1C, is there a chance it could, in theory, regrow?

 

Hiya Stephen. You know I have many Mandevillas (I had over 30 at one time) and the red Sundaville variety is the best with me, which is not a 'vining' plant like the Alice DuPont, Sundamandecos, etc, but more of a shrub. None of them have overwintered with me except the Sundavilles.

The only way to know is ... try ...

 

Might just be me, but its not a plant I've ever had much success with.
I dont think they like me.

 

I have tried to overwinter them before - just frost free. But they didn't survive. I later had a Google and realised that they need to be quite a bit warmer. http://www.ehow.com/how_2304495_grow-mandevilla-flowers.html This site says a minimum of 65F overwinter, though if you looked a bit further you could probably find a site that says a bit less.

There is quite a gap between freezing and 65F - so I wouldn't rely on it regrowing.

 

Kept mine going at 10°c (whatever that is), but it got very leggy and performed dismally the following year.

 

I may as well update this now, to my surprise a planted Sundaville, is still going under the sheltered area, we got down to +1C under there this morning (by far the lowest of the season), and it looks in great shape! Certainly against the expectation that it dies down at 10C!