Although these two long-loved iris are often confused, if you look closely it’s not that hard to tell them apart.
The most obvious difference is the way the lower petals of ‘Swerti’ curl into a point — except they don’t all do this all of the time, and sometimes a few petals of ‘Madame Chereau’ curl, too.
The lavender “stitching” along the edges of the petals is heavier and more prominent on ‘Madame Chereau’.
The flower shape of ‘Madame Chereau’ is longer and more refined than that of the broader, shorter ‘Swerti’.
The upper petals of ‘Swerti’ never quite come together at the top — which you can either consider a flaw or a mark of its great antiquity.
Learn more about this historic iris at