Long-lived clumps produce very dense sprays of pale sulphur yellow hooded flowers in spring and early summer, above attractive, bright green shiny foliage. If dead-headed, flowering will continue into the autumn.
For best results, sow seeds as soon as you receive them onto a good soil-based compost. Cover the seeds with fine grit or compost to approximately their own depth. These seeds can be very slow indeed to germinate, and may wait for spring before emerging whenever sown. Do not use artificial heat to try to germinate them as it will simply disrupt their germination mechanism. Please be very patient, and do not discard the seed pan.