I don't know what it is, but am posting that just so I can find out if/when someone identifies it - its very pretty.

I believe it’s from the Lobelia family x

Yes it reminds me of the lobelia flower- the mystery continues!

I thought it might be a variety of lobelia, perhaps Compton Pink but wouldn't bet on it.

Seaburngirl might know if no one else does...

I agree with above (didn't know before reading suggestions) and on looking up could it be Lobelia 'Compton Pink'?

Yes - it certainly looks like Lobelia 'Compton Pink'. Thank you.

sorry didn't get on the computer much yesterday. Busy sewing and then had daughter over for a barbeque. it didn't rain either! I also think Compton's pink. its a nice one too.

Its very pretty - said to be hardy but usually grown as an annual/biennial - does it behave like a perennial, does anyone know?

Isn't it lovely, and really unusual.

Hi, although I have never grown this, it was introduced in 2011, and is referred to as hardy to h4, needs a deep, fertile, moist but well drained soil, in full sun, which I haven't got in my garden, I have 1 small bed which has moist/well drained, and that is in shade until late afternoon in summer, and complete shade in winter, so I would think that's why it's usually grown as an annual, Derek.

Thanks Derek - I did wonder if it required that magical 'moist but well drained and plenty of sun' environment. I have the same trouble with Lobelia cardinalis - it gives up because the clay soil here is either too wet in winter, or dries out too much in summer.

Hi Bamboo, yes it is a magical combination isn't it, I don't think many people have it, I have clay too, but no matter what you do to it, you still have clay, if you're lucky you may be able to get it to drain better at best, Derek.

Mine is growing in partial sun/shade in my border adjacent to my summerhouse. It survived the winter (I think as I can't remember planting it this year!) but will keep an eye on it and see what is does in the winter.