It’s lovely, but what the heck is it??

It’s lovely, but what the heck is it??

I have a Wisteria growing in a tub. It's flourishing. There are some self seeded forget-me-nots growing in there too, but just recently another plant started to grow too. And grow. And grow. Now, it has flowered. It has really lovely white flowers that have a distinct scent. I like it a lot. What I would also like is to know a) what the heck it is, and b) how the heck it got in my tub! Can anyone help??? I've tried google but with no success, unfortunately. Evidence is here: Distance shot Photobucket - Video and Image Hosting A close up Photobucket - Video and Image Hosting Cross posted to my own journal - sorry if you get to see this twice!
My Scandinavian home

My Scandinavian home

The bedroom that I can’t stand unless I’m asleep.

The bedroom that I can’t stand unless I’m asleep.

Warp 9!

Warp 9!

Another batch of mysteries

Another batch of mysteries

Pretty pink AV

Pretty pink AV

my brownies bring all the boys to the yard…

my brownies bring all the boys to the yard…