Over twenty species of Helleborus are available for garden planting, including the Lenten Rose (Helleborus orientalis), Christmas Rose (Helleborus niger), and the Stinking Rose (Helleborus foetidus), as well as numerous cultivars. These hardy plants can be slow to get established, but given the proper conditions--moist, organically rich soil in a shady location in zones 4 and southward--they will develop spreading colonies which bloom reliably each year beginning in late winter, weeks before the earliest spring crocus.
Dig one hole for planting each hellebore plant 2 feet across by 12 inches deep, in a shady, sheltered location, using shovel. Dig out an extra 4 inches from the bottom of the hole and refill with a mixture of sand and soil if the area is not very well-drained.
Place 1 gallon of well-aged compost in the hole, then refill with soil dug from the hole.
Use shovel to create a small hole in the center of the refilled soil and compost of sufficient size for the hellebore plant. Remove plant from its nursery or shipping packaging.
Place roots gently in the hole. Hold the main stem at its base even with the level of the ground, and refill the hole around the roots. Tamp down firmly.
Water the helleborus plant regularly until new growth begins to appear, keeping the soil moist but not saturated. Top dress with additional compost before snow cover settles in, or in late autumn in more southerly regions.
In late spring, gently prune away leaves and stems that were damaged by winter snows or winds, using sharp pruners. Water the helleborus through the summer whenever the ground is dry, and top dress with compost again in late autumn. The plant should begin blooming annually by the second spring of growing.