|I'd call this a light violet blue on Hydrangea 'Let's Dance Starlight'|
|Clematis 'Blue Angel'|
|Siberian Iris 'Baby Sister' is what I'd consider blue.|
|Agapanthus or African lily flowers are very blue.|
Experts say true blue is rare in the horticultural world. What we often call blue is more correctly purple.
Sure, there are other flowers that provide a color very close to blue. But until the elusive blue rose is achieved, the largest, bluest flower in a Midwestern garden is the Hydrangea.
There are several cultivars of Siberian Iris that are blue, or at least the closest to blue a flower can get. Clematis also boasts a few nearly blue varieties.
I tried Agapanthus for the first time last summer. Planted in a pot, it seemed to take a long time to grow and even a longer time to open fully, but I officially want more. (Pause here for a one-hour online search.)
|Geranium 'Azure Rush' with Veronica 'Hocus Pocus'.|
A sport of 'Rozanne', called 'Azure Rush' has lighter blue flowers than the award winning perennial. It is said to be more compact than 'Rozanne', but just as long-blooming.