it in the flower border.? It is now 5 feet tall and just coming into bloom. Is this an Xmas 'mum, I am rather confused

Not sure but it could be the mild/wet weather. I've got roses in bloom that are usually died off by October xx

I iuve un Coastal NC and just now have Mums coming into bloom. It is the mild weather so far. The height? Well apparently the cutting reverted back to the original plant and not the one you took the cutting from. Seeds will do this too. They don;t always run true.

All mums are meant to bloom no earlier that September. The norm is Sept, Oct, and Nov. If you have one in December then the weather has not reached a freeze. Actually mums like cooler weather and a light frost.
They say keep all buds pinched until June but I have (buzz sawed lol!, I gave them a crew cut) the tops in July just to keep them from blooming too early.
I used to raise and sell them. (Missouri USA) I have never heard of any growing that tall except in California where everything grows big.
infact when we lived there my mom has some just about that tall.
I have grown them bigger than bushel baskets but only about 36" tall.
This is where I used to buy my plants
Home Page
http://www.bristolmums.com/

About
http://www.bristolmums.com/
More power to you take some pictures.
mums seen and grown all over North America actually originated here in Bristol!

Mums are usually trimmed about 3 times during its growing cycle to make them small and tight before they bloom. Sounds like you probably didn't trim and that the weather has caused it to bloom now.

Five feet tall?! That is confusing.

The Venerable Bede. Not a resident of Durham, are you?

the potted `mums` are treated with a growth inhibiter to keep them `pot sized`.it is know it`s normal size.