The Hellebore most commonly planted in gardens is Helleborus argutifolius, sometimes called the Corsican Hellebore or the Holly-Leaved Hellebore. Native to Corsica and Sardinia it is hardy in UK conditions. Easier to establish than H. foetidus which seems to flourish only on well drained chalky soils.
Both species have green flowers (not many plants do) but the flowers of H. argutifolius are more open and bowl-like. Unlike the Stinking Hellebore its foliage has a serrated edge, hence argutifolius meaning sharp-toothed leaves.