Lord, its infuriating isn't it, that the people who sell the plants give out the wrong advice. Chilean Potato tree usually refers to Solanum crispum 'Glasnevin', and its listed as frost hardy. Even were it fully hardy though, it would need hardening off before placing outdoors. Given its not fully hardy, and its in bud, should be kept somewhere out of frost and preferably a little bit warmer if you want those buds to open up into flowers.

If you plant it outdoors in May, choose a sunny sheltered spot - if this plant makes it through its first 4 or 5 years, I've known them become absolutely enormous and quite resilient to cold temperatures.

Wow Bamboo! Just goes to prove even us gardeners who have been at it a while don't read labels!
We have an old Leylandii hedge which had to be topped from it's at least 30ft height down to about 15ft with the side branches removed, leaving bare trunks. Up this I have planted just about anything that climbs to cover them, together with the existing ivy.
So..about two years ago I bought the Solanum Crispum 'Glasnevin' to run rampant through it. Reading your comment I dashed out to have a look at it and can happily say that it is in full leaf and doing it's rampant vine bit.
We are in Norfolk, not reknowned for a balmy climate, but this proves it can be hardy and it also grows at the base of huge Leylandii (so dry), mind you it is probably facing South-West.
It's been hacked back several times to conform to the space allowed and in need of it again! As you say Bamboo they can get huge.

Yea, there's one in a garden next door to a client of mine - the damned thing is real pain, I'm told its probably 25 years old, its trunk is 8 feet thick, its 12 feet high, and the growth spreads everywhere,in particular, dangling over the top of the fence. When I first went there, it ran the whole side of the client's garden, covering up everything they'd got growing in their own garden. It also destroyed the fence - once we cut it all back, the fence had given up the unequal struggle and the only thing keeping it up were the shrubs in the client's garden, which, of course, were all looking ghastly from being drowned by all that excess growth from next door. What a mess, a more or less total remove and replant job, and complete refencing job - so if it does survive the first two or three years, it needs controlling and a lot of space...