Howdy All, Just to raise another variable re flowering times....... it would also greatly depend upon what pollinators are about. If the desired pollinators were only in the area in autumn (for example) then those individuals of a species that flowered in spring or summer would not be pollinated, and therefore note reproduce...... which is a dead end result. Those that flowered in autumn when the desired pollinators were available would reproduce, so eventually only those plants in that genus that had the genetics right for flowering in autumn would be in existence in the area. Effectively a form of survival of the fittest, or at least survival of the "pollinator timing" fittest anyway. Just another thought to throw into the mix. It would obviously depend on plant types etc, which of course determines what sorts of pollinators would be needed, but it could possibly be a factor in the whole puzzle couldn't it? This is just a hypothesis of mine, so I have no idea of whether there is empirical data to support it....... 'twas just an idea of mine that I thought I might contribute. I hope this makes sense to those who are reading it. <grin> Cheers. Paul Tyerman Canberra, Australia - USDA Zone Equivalent approx. 8/9 Growing an eclectic collection of plants from all over the world including Aroids, Crocus, Cyclamen, Erythroniums, Fritillarias, Galanthus, Irises, Trilliums (to name but a few) and just about anything else that doesn't move!!