Hi Andrew, I've grown Delphinium parryi which is a lovely species and I still have one left. Ones I planted out are gone. I started some new ones from seed this year, but if I succeed with them, they could be hybrids. D. cardinale was difficult to keep going and to flower although I did get it to flower for a number of years. The others that continue to bring me pleasure besides Delphinium nudicaule and Delphinum luteum are: Delphinium patens, Delphinium hesperium, Delphinium decorum, and Delphinium variegatum. The birds sometimes bother the new leaves and a Delphinium decorum I didn't move before it grew through some wire I had put over the pots was especially spectacular this year when it was in bloom. It is a wonderful color. Plants I grew from saved seed of it are also doing well, but are a darker blue. Delphinium recurvatum is doing less well, but surviving. Mary Sue >Have you tried Delphinium parryi, the one with the large blue flowers?