Canada Post said it best

Those with Green hearts and minds will really appreciate the sunflower stamp that was issued on March 3 of this year:

http://www.canadapost.ca/cpo/mc/personal/collecting/stamps/2011/2011_jan...

"It’s hard not to look at the deep warm hues of the sunflower, with its wide open face and not smile. There’s something inherently happy about its blooms."

May millions of sunflowers bloom soon. May 2 would be a good time.