Wallflower Hardiness

Can you please tell me, if you know: Is Wallflower (S6690) a hardy plant? When would be the best time plant it in a Mediterrenean climate? When would be the best time to get good seeds?

Wallflower is native in Southern Europe where it is a winter hardy perennial. In zone 5 it can be grown as an annual, but it will only overwinter outside of a coldframe during warm winters. To get flowers and seed at the end of the first year (or at all in zone 5) the seeds should be planted as early as possible in the spring.