A joy for gardeners on still winter days is the slow emergence of the flowers of that jewel of the winter garden, the Hellebore. In contrast to the rapid flowering of many spring and summer flowering plants, Hellebores exhibit a determined longevity and individual plants can be in flower for several weeks – a blessing for gardeners in the depths of winter.
This is an adaptation of Hellebores to the tough cold conditions is which they flower in the wild. In the midst of an icy continental winter the Hellebore must keep each flower open in the hope of attracting its favourite pollinator, the bee, who are rather scarce at that time of the year.
The resurgence of interest in hellebores over the past 20 years or so has to some extent been driven by some fabulous developments coming from committed breeders of this genus. I say committed because the process of producing new colors and forms of hellebores is a slow and frustrating experience. Slow because a breeder needs to wait at least three years to see the results of each winters cross pollinating. Frustrating because seed-grown Hellebores are so variable and no two plants are ever completely identical.
However from the point of view of gardeners it is possible to divide up all the different Hellebores into three main groups. The first and most commonly grown type of hellebore is the very diverse group of garden hybrids known as Helleborus x hybridus, commonly known as the Lenten or Winter Rose. These are climatically the most adaptable of the genus and grow happily from Hobart to Toowoomba in inland areas, and in coastal areas as far north as Newcastle in NSW. Their natural variability has attracted the most interest from breeders and as a result they are now available in a bewildering variety of colors and flower forms. From white to near black, spotted or unspotted, single, semi double or double forms exist. With attractive glossy evergreen foliage and large showy flowers these are the show offs of the genus.
The second major group of hellebores are the taller growing more shrub like species. The floral display of this group is less colourful and showy but their height (typically up to about 75cm) and dramatic foliage make them valuable structural plants in the autumn and winter garden. This group includes Helleborus argutifolius (formerly Helleborus corsicus) with its wonderful spiny edged trifoliate leaves and its close but much rarer cousin Helleborus lividus with beautiful silver veined leaves on pink flushed stems. These two species will also cross to make the hybrid Helleborus x sternii, an extremely variable but tough plant. The other main species in this group is Helleborus foetidus, another foliage star, which is available in a number of different forms with varying foliage colour.
The final main group of Hellebores is made up of the very beautiful Helleborus niger, commonly known as the Christmas Rose, and its hybrids. Contrary to its botanical name, which refers to the colour of its roots, it has large glistening single white flowers. Rather unexpectedly Helleborus niger will hybridise with some of the taller shrubby Hellebores to produce some of the most sought after Hellebores such as Helleborus x ballardiae (the hybrid with Helleborus lividus) and Helleborus x ericsmithii (the hybrid with Helleborus x sternii). These hybrids often combine the best of both parents with the compact habit and large flower size of Helleborus niger and the attractive foliage colour and toughness of Helleborus lividus or Helleborus x sternii.
In the wild hellebores tend to be found in or near to deciduous woodland and this provides a clue to their best positioning in the garden. As they are often known as ‘shade plants’ some gardeners make the mistake of placing their hellebores in areas subject to very dense evergreen shade. One of the key things about hellebores is that they really appreciate plenty of light during winter when they are in full growth. So a position under or near deciduous trees or large shrubs is ideal. Alternatively a position where the plants are reached by the low winter sun will suit. Growth and flowering will be much better in such conditions.
Fortunately Hellebores are not high maintenance plants. One useful tip is to keep in mind that their growth cycle is pretty much opposite most other plants. They start into growth in autumn and really power away in winter when they flower and put on lots of growth. They then slow down by the end of spring and with minimal growth in the warmer months. It is therefore best to plant, move and divide hellebores during the autumn and winter period.
The most important annual maintenance task, especially for Helleborus x hybridus, is to remove old foliage (right down to the ground) and feed with a complete fertiliser in late autumn. Removing old foliage will show of the emerging flowers better and allow better air circulation about the plant in winter. For the taller shrubby Hellebore species the spent flower stems should be removed in spring. Watch out for aphids, which are the main pest of Hellebores, especially in the warmer months. Use whatever insecticide you prefer, but get good coverage under the foliage and be prepared for several applications.
Hellebores are well suited to the climate of south eastern Australia and are tough, drought and frost tolerant plants. Their stoic winter flowering and wonderful range of flower colours and forms make them truly a gem for the winter garden!
[This post is brought to you by Peter Leigh of Post Office Farm Nursery, a specialist hellebore nursery which mail orders throughout Australia (except WA). Visit Post Office Farm Nursery’s online shop or download their latest catalogue HERE]