I have measured most of last season's blooms. First number is the width of the bloom from fall to fall in their natural position, second is the height [in mm, with 25.4mm per inch]
Needlecraft-185, 80 [abt 7 1/4 by 3"]
Dusky Challenger-170, 100 [abt 6 1/4 by 4"]
many others are in the 5-6.5" range
Forgot to measure President Pilkington but remember it was quite large.