By Vincentdunne
Meath,
Ireland 
Hi, I thought at first this was Sweet Rocket but too early and wrong leaves. Any ideas. It is growing in Mt. Usher gardens in Wicklow. Brilliant garden if you can get to see it.
8 May, 2013
Answers
Yes, That's what I was going to say too; common name 'Honesty'.
9 May, 2013
My first thought too . . . White Honesty. (There's also a white H. with variegated leaves which I have: luckily seeds itself happily!)
10 May, 2013
Thanks for the answer, folks. It is amazing that I have lived with the common purple one all my life and did not recognize this. It seems to be rare as there are very few photos on google images yet this garden has hundreds of plants.
Thanks again, another one bites the dust!
10 May, 2013
We all do it Vincent . . . then when we're told the 'answer' we say "Oh, of COURSE!"
11 May, 2013
Is it Lunaria annua 'Alba'? It looks like mine, Vincent.
9 May, 2013