Starting perennials or biennials in the autumn

Well, I sow hardy annuals in September. My list is similar to last year....
Orlaya, sweet peas, clary sage, ammi, scabious, lychnis, cornflowers, larkspur.
I did foxgloves in July for next year. Last year I sowed snap dragons in feb. They have been fabulous so I'm going for a September sowing this year as well as a feb. Same for the other actually- I'm going to do 2 or 3 sowings to keep them looking fresh.

VC put up a post a few months back about sowing sunflowers and cornflowers - it seemed a little late for me. I will check out what month it was! I had already had substantial plants by then but I had the seed so gave it a go. The sunflowers open a couple of days ago, the cosmos haven't flowered yet but they are fresh and green and about to burst. The earlier sown ones are looking tired. So glad I tried it out.
I also read sowing more sweet peas at end of June gives you fresh flowers/plants late summer so well worth sowing less but a few times over the months.    
         
Some plants in the greenhouse early in the year from September sowings
I also do loads of penstemon cuttings - they root lovely. Pot on early and they are substantial plants by the end of spring.