clematis montana

Hi could anyone  tell me why my spring flowering clematis montana is flowering again in September.It was a little late flowering due to the bad weather (late spring).But i eventually had a good show of lovely white flowers. It only put on a bit of  growth after flowering,,and the leaves turned a russet colour.Now i have PINK flowers coming.I am only a novice gardener but i was told that the Montana is a spring flowering Clematis.I,m not complaining about this because it does look nice. just curious.So  any info would be gratefully received,thanks.

Probably just confused by a long, cool, wet summer with low light levels.

They often do, especially if we have had - as this year - a grey spring and summer, then some light and sunshine now - all the plant is interested in is getting flowers and seeds out there to continue its species - and it feels there might just be time enough. Sit back and enjoy. 

i have one climbing up through conifers. what a show in spring!!!! it is probably the weather which has confused it. my pieris have had several 'springs' . hope we have better weather next year

A similar thread here about rhododendrons-

http://www.gardenersworld.com/forum/plants/may-has-come-early/5696.html

I can recall other topics last year about daffodils in December-it seems to happen that every year that are some odd quirks- usually weather related

Thank you all, i thought it may be weather related, its nice  to have a bit more colour in september though..Yes Kathryn i hope we do too, could,nt do with another wet year. I had a swimming pool at the bottom of my garden in july.