Not much cultivated here but Bupleurum spp. are great plant fillers for the perennial garden. The yellow bronzed tinted tiny flowers surrounded by small bracts are borne in characteristic umbels that resemble somewhat the inflorescence of some Euphorbias.
A bright and cheerful plant that can be also used as cut flower. It may self-seed if it likes the place.
Germination: best at cool temperatures (around 15˚C) and the seeds need to be sown superficial; it may be slow to germinate according to some sources. Seeds were collected from the wild in the Chelyabinsk region (Southern Urals). Image from Carpathian Mts.