In no particular order those that deserve special mention are:
There is a runner up,
The winner though just nosed through the winning tape.
and it is Coronilla valentina ssp. glauca 'Citrina'. I bought this plant in 2013 from a talk I went to given by my good friend at Swines Meadow Farm Nursery I was taken with the plant when I bought it as it had a wonderful scent. I planted it up and it grew fairly well in its first year or two, but this year it has really matured.
It is a bit sprawly and likes a bit of a hair cut in the spring to keep it from straggling about too much. It has flowered pretty much all year, well in my mind it has anyway. It certainly seems to have been flowering every time I have noticed it. It gets lots of points for that alone. It sprawls well, I like plants that sprawl well, popping up through other plants, not smothering but adding to the overall effect.
What makes this plant win though is the scent. Every now and again I will be weeding away in the border, or just wandering past and I think 'what is that wonderful scent?'. I stop and look around and then I realise it is the Coronilla, I smile and resume whatever it is I am doing. This is what makes it the winner this year. You may now applaud enthusiastically.