Oddly, the Royal Horticultural Society includes 'Australian fleabane' as another common name for the Erigeron karvinskianus, which is most commonly known as 'Mexican fleabane', despite the plant being considered a weed species in Australia, according to Wikipedia.
In this instance, in the London garden of one of my pet-sitting clients, it was not considered a weed, but a welcome and cultivated part of the garden.
I like that it appears to bear both white and pink flowers on the same plant (please let me know if I'm wrong!)
