Lent A Williamson is the most vigorous I have ever had, almost in the weed category. Indian Chief and Iris Germanica come in at a close second.
Helen Collingwood, Apache, Joy, Mary Frances and Gypsy Queen all grew great on the NNE side of my former house, getting only morning sun for a few hours in the summer. Edenite, Prairie Flame and Prairie Sunset were less vigorous in that location but did blossom and increase. Needlecraft did poorly there.
Others were in the low average to poor range of growth even in the full sun while their neighbors grew great, so location, sun, soil and everything else surely makes a difference. Each iris variety seems to prefer specific conditions, so what we want growing next to each other may not work out well.
