The fleabanes are a large genus, over 400, half of which are native to North America, but not grown as much as asters and relatives. However they provide aster-like flowers and colour much earlier in the year (late spring) and later on if cut back hard. Good for cut flowers and an excellent nectar source for insects. Good garden worthy species are E. karvinskianus and E. glaucus. Grow in a reasonable soil with no overhead competition.
As with all 'daisy-like' flowers, the disc-flowers in the centre of the flower head produce nectar and pollen that are attractive to insects. The flower heads of the many erigeron species that have the 'daisy' form are particularly favoured by bees and hoverflies; those of the 'weedy' relatives, with small flower heads are probably of lower importance. Some species eg E. glaucus are of additional value as effective ground cover in a dry or coastal garden, retaining water and providing shelter for invertebrates.