I have a blue fleabane in my herb garden which is quite well behaved. Looked up my native plant list for Washington and found 6 different native erigerons, so definitely some diversity. Near as I can tell, my tame one is E. speciosus 'Azure Fairy'. I do see some pretty blue daisies along our road shoulders, which may be a form of erigeron, I'll have to look closer when they bloom this year.
