When looking through the 802 "Iris" images at Acclaim Images.com this A Blue Iris Against a Soft Green Background was a favorite.
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Description:
A Blue Iris Against a Soft Green Background
Stock photo of a blue iris against a soft green background with distant blue irises and selective focus.

Some related terms for more images:
blue,  bloom,  iris flowers,  blue flower,  flora,  blossom,  botanical,  floral,  blue flowers,  studio 33 photography,  botany,  gardens,  blue iris,  irises,  blue irises,  blooms,  florals,