My Michaelmus Daisies pictured here no longer exist.  They suffered winter-kill three years in a row, and never recovered.  I seriously doubt their claimed hardiness.  I grew some new plants last year, and am hoping they survive the winter.  I believe they began blooming in May.  They only bloomed for a short time, but were one of the prettiest flowers in my garden.  I also recall them having a pleasant odor when sniffed from close proximity.  The name "Michaelmus" also applies to other species of daisies.