My friend, Jean, identified it as Dicentra as well. Thank you so much. It has to be as I have several in the garden. Funny thing is that I have them in 2 other places and both sunny. This worked up its energy in a trough planter behind my butts together with a bamboo and a hebe. All three coming up very happily, even being shaded by 3 huge butts!
I thought it was a Romneya Coulteri. I should have known pearl did not spring out from nowhere! It's a lovely plant and I have my heart set on a yellow one!