Japan nuclear scientists have used cyclotron to irradiate the famous cherry blossom tree to see if they could turn up useful mutations.
It seems they have, making one which can bloom more than once a year.
Problem is, this could cause cultural mayhem, given the amount of partying that happens during cherry blossom season.
Interestingly, though, they are blooming earlier every year:
Last year the "blossom front" (constantly reported on television weather programs) reached Tokyo five days ahead of schedule at the start of April — the fourth year in a row that it has been early.