Are you sowing them outside or do you have an indoor place you can keep seedlings for the winter? In the 'wild' the plants would drop the seeds in fall, they would lie dormant through the winter and germinate in spring. Sometimes even seedlings will survive winter if they germinate before it gets too cold.
Commercial growers would sow now, and keep the seed flats cool-ish once the seeds germinate. Cool greenhouse conditions would apply, and you will probably have blooming size plants by the end of next summer if you do this. In front of a glass patio door might be a good place to bring the seedlings along starting in maybe February. Cool but bright light.
In either case, I would say the time to sow those seeds is now, or soon!
