Slightly taken aback to find this at Branklyn. I have kept this for years in my daughter's Caithness garden. It does set seed from a single plant but have no idea where the garden in Perth obtained this from or why on earth it is called James Cobb! It is one of three distinct forms of Meconopsis grandis that I have  and  always called it Early Sikkim. As I write the first blue poppies are out in the garden of my Invergowrie daughter which is a very early date.