Hellebores, Hellebores, Hellebores

by Tony Avent, Plant Delights Nursery, Inc.

There are few perennials that can rival the year round interest of hellebores...often called Christmas or Lenten Rose. These staples of the winter garden are among the most coveted of garden plants, yet they are still relatively unknown outside of plant enthusiast circles. Perhaps the fact that they aren't good mass market plants attributes to the fact that they will rarely be found at the lower end mass merchants.
Hellebores have long been grown in gardens, although originally for their medicinal properties. Hellebores are filled with alkaloid toxins and have long been used both as a poison and a purgative. Because of their toxicity, hellebores are consequently prized as "deer resistant" garden plants for areas with wildlife pressures.
Hellebores are primarily European natives, being found in open meadows in Bosnia, Croatia, Slovenia, Turkey, Greece, Italy, and even 1 species in China. We would like to salute UK plant explorer Will McLewin who risks his life every year to trek through these regions gathering hellebore seed and researching the genus with a rarely seen dedication. While naturally a full sun plant, hellebores make superb specimens for the woodland garden. In fact, they will thrive in the darkest garden conditions including at the base of black walnut trees.
Hellebores are often found native in alkaline soils, but adapt without a blink to our very acid woodland soils. As for fertility, all of our hellebores are fertilized with an organic slow release blend in the spring with everything else in the garden. For the lazy gardeners, however I have seen spectacular gardens of hellebores that have never seen a drop of fertilizer.
A true testimonial for the durability of hellebores are those growing at the old Raleigh garden of NC's famed garden writer Elizabeth Lawrence. Her Raleigh home, from which she moved in the 1940's is still filled with wonderful clumps of Helleborus orientalis hybrids. This is after being used as a fraternity house for nearly 50 years!
As for drought and neglect tolerance, that story speaks for itself. Hellebores are sensitive, however to too poor drainage and too much moisture. Although H. orientalis hybrids are very forgiving, many of the other species are not so, and will quickly bite the dust if planted in a soggy site.
Hellebores are divided into two basic groups, caulescent (with stems) and acaulescent (without stems). The caulescent species include H. argutifolius, H. foetidus, and H. lividus. The acaulescent species include H. orientalis, H. niger, H. purpurascens, H. viridis, H. atrorubens, and all others.
The most commonly known of the acaulescent species is Helleborus orientalis, the Lenten Rose. Actually what everyone grows in their gardens are not really H. orientalis, but hybrids involving H. orientalis. The true species is actually quite difficult to grow, while the vigor of the H. orientalis hybrids make them one of the easiest of garden plants.
Each H. orientalis hybrid makes a clump to 2' wide by 15" tall of thick evergreen hand shaped leaves. In late winter, the 12" tall flower spikes emerge from the underground rhizome. As the flower spike tops the leaves (which flatten out in the winter), it branches, producing a cluster of silver dollar size flowers. Actually, what we call the flower are not petals, but a modified calyx. This accounts for the seeming longevity (3 months) of the "hellebore flowers"
The flower colors of the Helleborus orientalis hybrids are what enthrall plant collectors, as each one is dramatically different. The basic color range is from black purple to red purple, to white, pink, and even yellow. The patterns on the blooms add even more to the fun, with breeders working to add different colored speckles both to the center and the edge of the flowers.
Now, hellebore breeders are also working on flower shape...some opting for cupped flowers, while others work toward large flat open flowers. Some breeders prefer up facing flowers, while others prefer the natural bell like form, where only the colors are seen on the back of the flowers.
Purchasing named varieties of hellebores has always been a difficult task for gardeners. Not only has most of the hellebore work been done overseas (the late Helen Ballard - Germany, Elizabeth Stragmann-England, and the late Eric Smith-England) When a breeder would develop a nice variety, everyone would want a piece. While hellebores can be divided, the process is never going to be viable on a large commercial basis. This prompted both high prices, and unscrupulous nurserymen to sell seedlings as the "true cultivar". In fact, each seedling is different, and rarely does the flower color of the seedling match that of it's parent.
Only in the past few years have some growers started to sell hellebores by flower color. This is done either by divisions, where all the plants are identical, or by growing and flowering a large batch of seedlings and then sorting them by color. Obviously, the time involved in this process (2-3 years from seed to flower), the price is often out of reach. For a slightly less price, you can buy unflowered seedlings, which thanks to careful inbreeding, should have a higher percentage of colors similar to their parents.
Another of my favorite species is the Christmas rose, Helleborus niger. While rumored to be impossible to grow in the south, the large clumps in both my garden and others throughout the south confirm this rumor to be unfounded. Indeed, H. niger is not as easy as the H. orientalis hybrids, but still easy enough for most gardeners. H. niger has darker green and much smoother leaves than the H. orientalis hybrids and begins flowering much earlier. For us, H. niger is usually in flower by late December or early January. The flowers in this species are pure white, and arise similar to the H. orientalis hybrids.
Of the other acaulescent species, H. purpurascens (purple flowers), H. atrorubens (very early purple flowers), and H. viridis (green flowers) are good easy to grow choices. Unlike H. niger and H. orientalis, these species are often deciduous, so don't panic when they disappear in the winter..
I am also a big fan of the caulescent (stemmed) species. My favorite is certainly H. foetidus, the so called "stinking hellebore". While folks often expect smelly flowers, the only part of the plant that is foetid are the leaves, which leave an unpleasant odor on your hands if you fondle your hellebores too much.
H. foetidus has very dark green leaves with long "fingers" These leaves clothe the 18-24" tall stems. As a background plant to hostas and ferns in the summer garden, H. foetidus is marvelous. Then as the perennials of summer go to sleep, the evergreen clumps of H. foetidus remain and become the focus of the winter garden. In early winter, the flowering stalks emerge, opening open around the first of the year with 1' tall spikes of green bell like flowers. These flowers remain attractive until early spring.
Thanks to gardeners in England, there are now many different forms of H. foetidus available. The most popular is H. foetidus 'Wester Flisk' with red stems and slatey green leaves. H. 'Green Giant' is much larger and can often reach 3' tall. H. foetidus 'Autumn Moon' is a form that we named from my friend John Elsley that consistently is in full flower in October. Other forms boast more cutleaf foliage, dark slatey black leaves, and a variety of other unique characteristics.
H. argutifolius is also a good garden plant. Making a 2' tall x 2' wide evergreen clump, it is adorned with very serrate trifoliate leaves. In late winter, it is topped with stalks of creamy light green flowers. The most tender of the caulescent species is also the most beautiful, H. lividus from Spain. The silver and green patterned leaves would make any gardener covet this gem. Although it has been hardy in our garden for 7 years, we are at the northernmost end of the range. For those a bit further north, try the hybrid H. sternii (H. argutifolius x H. lividus). This hybrid combines the beauty of H. lividus with the hardiness of H. argutifolius.
Hellebores are easy to propagate by seed. In fact, most folks just let the seed fall on the ground, and in a few years, you will have enough hellebores to spread through the neighborhood. I like the fact that the seedlings stay right around the base of the parent plant. This is particularly useful with H. foetidus which is often short lived (3-5 years), but by seeding in place, the plant will never leave your garden.
Hellebore seed are easy to sprout if they are planted fresh, but not if they are allowed to dry. When sowing the seed in pots, do so as soon as they are ripe, and keep the pots outdoors until Christmas, since the seed need a cold treatment to sprout. The seed pots can be brought indoors at this time and they will sprout immediately. If left outdoors, they will sprout in late winter.
For further reference on hellebores, we recommend the following books:
The Gardeners Guide to Growing Hellebores by Graham Rice and Elizabeth Stragmann (Timber Press)
Hellebores by Brian Matthew (Alpine Garden Society, UK)