So ... I remember being extremely tired when I planted these rhizomes last year. I labeled this one 'Sweetheart Ring', which it clearly is not. I know it is either TB 'Blue Rhythm' or 'Missouri'. I cannot find good info about height on these two. I would be inclined to say it is Missouri except that it is not particularly fragrant and Missouri is supposed to be extremely fragrant. No purple at base of foliage. Opinions anyone?

Height won't help as both are in the over 36" category. Both have beards with the color change in the throat so another "non-help."
The darker veins at the haft seem to favor Missouri. It also appears to be a bit deeper in color.

Missouri opened yesterday. The differences are obvious when you see the two irises side by side. Additionally, there is the matter of fragrance. Neither of these iris is as fragrant as the descriptions would have one believe. 'Blue Rhythm' is supposed to have a citrusy smell. This morning I sniffed a bud of BR that was just opening. Definite citrus smell. The fully opened flowers have faint vestiges of scent. According to the AIS 1939 checklist, Missouri smells like strawberry and lily of the valley. I wouldn't go that far. The smell is sweet but not easily described IMO. Check out Terry Jones's blogspot for an interesting article: http://historiciris.blogspot.c.... I got the information about scent from him. I believe he died early this year, so I am not sure how much longer the blog will be available.

Blue Rhythm (on left) and Missouri (on right)

Looking good. Never put too much into the fragrance, or odor for some, of irises.

DaveinPA said:Looking good. Never put too much into the fragrance, or odor for some, of irises.

Still, if they "smell nice", I would consider it a nice bonus.