It would be expected that the seeds you have planted, will germinate in 14 -21 days and ideally grow to 15cm or so, slowing as the days reduce and cool. They will then become semi-dormant and may benefit from cloche cover, to reduce wind damage and the effects of heavy rainfall. Slug control is recommended. Once Spring establishes, they will hopefully grow away and flower to co-incide with early pollinators, in April
If they do not emerge within the timescale suggested, I would dig a few up to discover their condition, preparing to start replacements in pots to plant out in February. Mice and voles can also explain no-shows!
Personally, I wait to pursue the fall back option, my site is exposed to wind and voles.
