Helleborus x sternii is a cross between Helleborus argutifolius (Corsican Hellebore) and Helleborus lividus (Majorcan Hellebore), named after Sir Frederick Stern, first brought to public attention in 1947. It is an herbaceous or semi-evergreen perennial with purplish stems and pinkish mauve upright flowers. The flowers and stems are a pale green when they first appear.
As you’ll discover if you start researching hellebore, everyone describes the stems and flowers slightly differently since they change color over time once they are open.
Helleborus x sternii has 3 dark green toothed leaflets on each stem. Each leaflet has pale green veins. The leaves are purple underneath.
Helleborus x sternii will take from 2-5 years (depending on growing conditions) to reach it’s full size of about 1 1/2 feet tall and equally as wide. Partial shade, a little shelter and moist alkaline soil will make this hellebore happy. Be careful when pruning the old leaves or using for cut flower arrangements because Hellebore is toxic and can irritate your skin or make you sick if ingested.
Helleborus x sternii ‘Blackthorn Group’ can be propagated by dividing. If propagated using seed you will not get the true strain.