MARY ETHEL ANDERSON in my garden is quite incredible in its flowering duration (a friend, who will remain nameless, insists on calling it Merry Ethyl Alcohol). The longest period so far is 9 December 2011 to 17 May 2012, 160 days (>5months). I am confident it will beat that in 2013-2014 having already kicked off on 8/10/2013. I don't believe there has been a day since then when there hasn't been any buds on any of the four clumps. Interestingly, it was a terrible performer until I broke it up into four fans, moved and replanted. Then it just went mad.