As lovely as Hellebores are they are not the easiest plant to grow. I recently bought some myself and was given a growing guide with them. The following information is from both the growing guide and my own personal experience with these plants.
The correct climate and planting location for Hellebores in Australia
In Australia Hellebores can be grown in Victoria and Tasmania. They will grow as far north as Sydney but they are ideally suited to the colder weather of the Southern states. As you may have guessed these plants are not effected whatsoever by frosts. Hellebores do not like sandy soil or waterlogged heavy clay soils so something in between is needed. The planting position of Hellebores is important. They need to be shaded in summer and have as much sun as possible in winter. This is why people always tell you to plant them under deciduous trees.
Hellebores have very fast growing root systems so you need to plant the as soon as possible. They put on most of their growth in winter so planting them as early as possible in the cool seasons gives them more of a chance to establish themselves. Plant them about 60cm apart and loosen the roots before planting. Incorporate organic matter into the soil before planting and water in afterwards.
When new growth starts to show through in late autumn remove all old growth. Late autumn is also time to feed these plants as the main growth occurs in winter. During the warm months inspect the plants for aphids. Hellebores usually need 2 to 3 years to establish before flowering will occur.
If you follow these instructions your Hellebores should thrive. The main point is the planting location. They really do need as much sun as possible in winter to put on a good show of flowers. Some people have told me that they need full sun but in my experience I have seen Hellebores flowering well in locations with an eastern aspect so they would only be getting full sun for half a day. Good luck!