its everywhere, we unknowingly transplanted some into our garden when we moved in because it looked nice flowers, we got it from a neibour that didnt know what it was, :doh: took us 2 years to get rid of, it took a shit load of weedkiller and a hell of a lot of digging to get rid of it all.
then we gave it to the council in their "green waste" bin at the dump.
my mother in law has some in her front garden likes the look of the flowers . like u say. bummer to get rid off...she dont no where it come from but it looks nice...she says.....