I don't know, Terese, I never tried them. I have only one aster, "Bluebird" which is propagated vegetatively, doesn't set seed.
I thought asters were supposed to be easy? Clothier says
Aster alpinus, amellus, azureus, coloradoensis, cordifolius, delavayi (diplostephoides), farreri, laevis, lateriflorus v. horizontalis, linariifolius, novae-angliae, novi-belgii, oblongifolius, pilosus, sagittifolius v drummondii, sericeus, sibiricus, simplex, tongolensis, and x fricartii , Sow at 20ºC (68ºF), germination slow
Aster bigelovii, divaricatus, ericoides, linosyris, macrophyllus, ptarmicoides, puniceous , turbinellus, and umbellatus, Sow at 20ºC (68ºF) in light, if no germination in 3-4 wks, move to -4 to +4ºC (24-39ºF) for 2-4 wks
Aster stracheyi , Sow at 20ºC (68ºF), germinates in less than two wks
That info sounds like they should be perfect candidates for wintersowing. Have you tried sowing in both spring and winter?
I tried platycodon for 5 years, never had one sprout. Everybody says they're easy but they don't seem to want to be in my yard.
Karen
