Propagation
Sow seed when ripe in pots and place in an open frame to germinate and keep moist.
Division of the clump during spring

Botanic information
Leaf: The flat blue green long linear leaves have margins with evenly spaced stiff bristles. 

Flower: The small campanulate flowers are yellow in bud and open with 6-whitish lanceolate petals and has a yellow centre. The flowers are arranged in a terminal cyme that is held above the foliage on a branched scape up to 450mm (18in) tall and appear during spring.
Note
Both the buds and stems are heavily pubescence and the flowering period may extend into summer.  

Fruit: