Help identify a plant we has last year

Looking to find out if a plant we brought last year was aperennial plant or a bedding plant, we have moved over winter and allot of plants didn't survive the move, we really want this plant again as it seemed to flower all summer and spread really really well,
It's the purple trumpets under the big window

 

I think it's probably a petunia, by the look of things!

 

Aww fantastic can we use to to grow up a small fence pannel?

Thank you to both of you

Will it grow back next year or will we need harvest the seeds to grow back?