GordonHawk said:Is there a date stamp imbedded in the genes..how do they know/ remember that date
This is something I have observed and it is fascinating. The synchrony of certain plants can be remarkable. I think the embedding mostly has to do with pollination. If you only have one chance to make the magic happen, it really helps to agree about the date of the date.
Like Daisy says it has to do with the day length and stuff like that, but this pollinator angle really explains a lot of stuff that we observe with flowers.