Late Fall into Spring would not be the same without the Helleborus argutifolius. The Holly Leaved Hellebore is the largest of the Hellebores. The silvery spiky foliage of the Corsican Hellebore is easy to find compliments from other shade plants. Helleborus argutifolius flower spikes, with their white flowers, can grow 2-4 feet tall. Helleborus aftutifolius is hardy down to 0°F