Posted: 21/09/2013 at 13:54
You can sow quite a lot of perennials now Asho. There are many that need to be cold in winter before they will germinate. Astrantia, aconitums. aquilegia, though I sow that in January now, still in an unheated GH though.
Have alook on here
It lists lots of seeds and when it's best to sow them.