I have seen so much variation with Seattle that anything is possible. Lovely flower - they seems to change color with the weather.

Anna, I don't want to burst your sporting bubble, but Seattle has behaved so weirdly over a vast geographic expanse this year that I wouldn't rely on it to be a sport. People here in the NW US have complained it was a "non summer," with cooler and wetter conditions than usual, but others far away have had the same results on this variety.

Either Seattles have been all yellow, or yellow with a hint of a white tip on a couple petals or not blooming at all.
Here is a shot taken today: the best Seattle representative being on the left, and that is the only normal looking one I've had all year. It's just bizarre!
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Here is the first bloom off the same plant. Nothing at all like the Seattle I've enjoyed in the past.
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Thanks everyone, especially Poochella - always so informative. I guess I won't bother with any cutting or rooting.