All About Hellebores

Hellebores are an incredible group of evergreen perennials for gardeners from zone 3 to zone 9. In warmer zones, they are winter and early spring-blooming plants providing colour from late November through April. In colder zones, they bloom in late winter and early spring as soon as the snow melts. In any zone they provide interest when most other plants are soundly dormant bringing forth the first major burst of colour for the season.

The Christmas rose, Helleborus niger, is the first to bloom. In mild winter climates it could even be considered a late season bloomer instead of an early bloomer since new cultivars can begin blooming in November and December. In colder regions they bloom as soon as the snow melts. They are followed by many new hybrids including the Frostkiss Series, the Helleborus Gold Collection, the Ice ‘n Roses Series, and rare hybrids such as ‘Rosemary’ and ‘Mme Lemmonier’. Next come the Lenten roses, Helleborus x hybridus, which offer the widest range of colours, flower detailing, and flower forms.

There are hellebores that are better in shade. There are others that are better in sun. Some are great in containers. Others are best in the ground. There are plants with outward-facing flowers and plants with nodding flowers. All hellebores are easy to grow, long-blooming, and most are long-lived, especially the Lenten roses which can last for decades and even a human lifetime. They bulk up over time getting bigger each year and putting on more and more impressive displays for months on end. Their evergreen foliage makes them useful plants year-round. In all, hellebores are simply one of the most important and useful genera in the entire perennial world.

The Christmas Rose

The Christmas Rose, Helleborus niger, has a long tradition of use in the cultures of northern Europe where the plants were brought indoors during the Christmas season to decorate the house. Their pure white blooms and central cluster of golden yellow stamens seemed the perfect accent for the holiday season and to brighten the house and garden during the darkest days of the year. The Christmas rose has quite dark green, leathery leaves and flowers that are outward facing. In mild winter climates it usually comes into bud and bloom from late November to mid December continuing into the new year. The Helleborus Gold Collection has revolutionized the Christmas Rose with numerous cultivars all starting with the letter “J” that are particularly robust in both foliage and flowers. The bloom time for these plants can run from December to April! Each cultivar has it’s own valuable attributes. ‘Jacob’ is the original with a subtle fragrance and good tolerance for being brought into the house. ‘Jonas’ and ‘Jesko’ are also good for this purpose. ‘Jonas’ possesses a few extra petals giving a fuller look to the flowers. ‘Josef Lemper’ is the largest-growing of the HGC Christmas roses and is best in the landscape.

The Christmas rose is the hardiest of the hellebores. Reports from northern Ontario and Alberta suggest that H. niger is hardy to zone 4a for sure but probably to zone 3a with a good thick mulch of leaves and good snow cover.

The Stemmed Hybrids or Snow Roses

In recent years an entirely new hybrid group has been developed from the caulescent or stemmed species from the Mediterranean (H. lividus and H. argutifolius) crossed with the Christmas rose, H. niger which hails from Switzerland, southern Germany, northern Italy and east to Croatia. H. foetidus has also been used. These intergeneric hybrids offer leathery leaves on which sit clusters of outward-facing flowers mostly in shades of white, cream, pink, and dusty rose. These hybrids are more tolerant of full sun and also do well in pots or the ground whereas the Lenten roses prefer part sun to shade and don’t enjoy pots beyond a few years.

The first cultivar to make waves of this new hybrid group was Ivory Prince but more recently the Helleborus Gold Collection has introduced many superlative cultivars that have captured the imaginations of gardeners and designers. Since then the Lenten roses have been crossed into this stemmed hybrid group — a feat previously thought to be impossible — producing outward-facing flowers that sit on top of incredibly mottled foliage in deep, bold colours once the exclusive domain of Helleborus x hybridus. These new hybrids are known as the Frostkiss series. Another series also employing this same type of cross is the Ice ‘n Roses series. These are huge plants with outward-facing flowers sometimes reaching nearly two feet tall and sitting above very large and very dark green leaves. These new series are continuing a long tradition of innovation in hellebores that continues to greatly benefit the gardening world.

The stemmed or snow roses are usually listed as zone 5 hardy. However, gardeners are having success in zone 4 where they are protected by a good mulch of fallen leaves and good snow cover.

The Lenten Rose

The Lenten rose, Helleborus x hybridus, is the last group of hellebores to bloom. In coastal BC the buds usually form in late January opening usually in mid to late February. Flowering continues into April and sometimes May. In colder zones the Lenten roses will bloom in early spring after the Christmas and Snow roses. Helleborus x hybridus is usually listed as zone 5 but many gardeners have been having good success with a good mulch of fallen leaves and good snow cover. Some gardeners are even blooming Lenten roses in zone 3! Our production manager used to live in Winnipeg where she successfully grew and bloomed Winter Jewels hellebores. In fall she would mulch the plants with a deep pile of fallen leaves and then place an upside down styrofoam cooler over top of them. Then, through the winter she would shovel snow off of her patio over top of the hellebores created a deep mound of insulating snow. In the spring she was rewarded with beautiful flowers.

H. x hybridus offers the largest colour range and the most diverse flower forms of all hellebores with nearly every colour of the rainbow and single, semi-double, and double forms. Most Lenten roses are grown from seed strains which has the benefit of producing an incredible diversity of flower colours and patterns that are well worth collecting. There are others that are tissue cultured so that every plant is identical.

The Lenten Roses: Strains versus Cultivars

Traditionally every Helleborus x hybridus offered has been derived from seed strains since hellebores bulk up slowly and resent being divided. Seed strains are carefully bred lines that are maintained over time to ensure as much uniformity as possible in selected characteristics which include flower and foliage colour, flower size, flower set, degree of doubling, petal shape, petal spotting and picoteeing (having a darker edge), colour of the nectaries, habit, vigour, and height. For instance, the Winter Jewels Onyx Odyssey strain is bred from carefully selected hand pollinated plants by Marietta O’Byrne to maintain purple-black to near black flowers with a near 100% rate of double flowers on strong, vigorous plants. Other strains such as the Royal Heritage Strain, the Lady Series, and the Winter Queen Strain are more varied in their flower colours and forms.

are derived from less meticulous breeding. These represent good entry level plants for the landscape but produce flowers of lower quality than the Winter Jewels and other well bred strains like the Honeymoon and Wedding Party Series.

Different strains have been bred with different qualities of genetic material as starting points and differing levels of attention and skill from their breeders. Consequently, not all strains are created equal. Strains with meticulous breeding, such as the Winter Jewels strains, the Wedding Party series, and the Honeymoon series, for instance, are bred to extremely high standards while other strains are bred to more average standards. Compare the flowers between different strains and you will quickly understand the difference. The groups with less meticulous breeding are good entry level plants and good for mass planting in the landscape but the highly bred strains are outstanding treasures that you will want to give pride of place in the garden.

Despite breeders’ efforts, hellebores are complicated. They are hybrids of numerous wild species so their genetics, and hence their breeding, are difficult to understand. Consequently, and magically, no two hellebores derived from a seed strain are the same. When selecting from a strain you should compare the plants and their flowers to find the individual(s) that you most love! They are all different and all have their own particular charms. However, do remember that if you purchase a plant that is not in flower it is impossible to know exactly what you will get!

More recently, diligent labs have discovered how to micropropagate or tissue culture hellebores. The resulting plants are all identical. The very best plants from the best breeders are now being selected for larger scale production. This means that special plants that never would have left the breeders’ or their close friends’ private gardens are now becoming available to the general public. Even if these cultivars are not in flower, you will know exactly what the blooms will look like when your plant reaches maturity. Tissue cultured cultivars take away a bit of the magic of finding your very own gem but they will all be outstanding plants.

To differentiate between hellebores derived from these two different methods of propagation we use the correct botanical formatting when possible to differentiate between these two groups of hellebores. Seed strains are written without single quotes as in Helleborus Mrs. Betty Ranicar or Helleborus Winter Jewels Sun Flare. Cultivars produced through tissue culture will have their names surrounded by single quotes as in Helleborus ‘Tutu’ denoting a true cultivar where all plants are uniformly the same. 

Singles, Doubles, and Anemone Centres

Though superficially the single hellebore flower looks like a normal flower, it’s actually a bit different than what you would assume. What we think of as the five hellebore petals — the colourful white, pink, red, purple, near-black, green or yellow structures that get us most excited about these plants — are actually the sepals, which on most other plants are green and protect the petals. The petals of hellebores are actually very small green, yellow, burgundy, or black structures that form a ring around the stamens. In this case they are called nectaries and are important for attracting pollinating insects.

It is fortuitous for us as gardeners that the colourful part of the hellebore flower is the sepal. If you think about flowers in general, the petals usually have a short lifespan while the sepals can last for months and sometimes are even present on the fruits, as with roses and rose hips. The long-lived sepals of hellebores are what gives us the months of colour that we so appreciate.

Double hellebore flowers occur when the nectaries become petaloid and take on the same colour as the sepals (unlike in most other double flowers where the stamens and pistils become petaloid and the plant becomes infertile). The form of the double hellebore flower usually consists of the five sepals which cup a number of smaller, usually pointed and more numerous petals.

Anemone centred flowers occur when the nectaries become partially petaloid, take on the colour of the sepals, and surround the stamens like a ruffled ring of baby petals.

Single petaled plants are the most common since this is the natural form of the hellebore flower. Doubles are the second most common and anemone-centred flowers the most rare. Perhaps this is due to the greater interest in double flowers, though crosses of anemone-centred plants tend to produce a lower percentage of anemone-centred offspring than similar crosses with double flowered plants that produce double flowered offspring. Let’s just say that to have a double flowered hellebore is rare and special. To have an anemone centred plant is even more uncommon and well worth hunting for on the tables of blooming hellebore flowers.

Investing in Hellebores

Hellebores cost more than the average perennial because they either have to be tissue cultured or grown from seed which takes 2-3 years to achieve a blooming sized plant. However, they are a great investment for your garden. Hellebores provide colour for two to three months when you most need it, they are evergreen year-round and, since they are extremely long-lived, they will be with you for decades – you can even pass them on to the next generation in your will. Carol, a friend of the nursery, wore a corsage to the Hellebore Hurrah! one year of a hellebore flower that has been in her family since she was a little girl! The plant was brought back from England by her mother in the 1960s. Hellebores are well worth the investment for your garden and for your containers.

Cultivation

Hellebores are easy to grow in most garden situations. They prefer evenly moist but well-drained soils but are tolerant of drier conditions once established. An annual top dressing of two to three inches of compost in winter or early spring is all hellebores really need for fertilizer as long as you’ve started with reasonably good soil. You can also fertilize with an organic or a conventional slow release fertilizer. There are two times of the year when you should fertilizer hellebores. The first is towards the end of the flowering period when plants begin to grow new foliage and plantlets within the clump. Fertilizer at this time will encourage strong new growth and bigger, fuller clumps. The other time to fertilize is in the fall. In September and October hellebores begin to initiate buds deep down in their crowns. Fertilizer at this time of year will encourage more flowers in the winter and spring.

Helleborus x hybridus can be grown in full shade but will grow the fastest and have the most flowers in part shade to part sun. A situation with morning sun is ideal. Where the soils are rich and evenly moist, these hellebores can also be grown successfully in relatively full sun though protection from the hottest sun of the day in the afternoon is advisable. The stemmed hellebores such as H. foetidus, H. argutifolius and the hybrids x nigercors, x ballardiae, x sternii, and x ericsmithii as well as the Frostkiss and Ice ‘n Roses series prefer more sun and do best in a part to full sun situation. If not given enough light they can become floppy and will require staking. They could also be shorter lived if planted in shade.

At blooming time many gardeners will remove last year’s leaves from the H. x hybridus types so as to see the flowers better. The plants do not require their leaves to be removed. It is an aesthetic choice. However, removal of the leaves might help to decrease the incidence of pests such as aphids and fungus, if these are an issue. Normally, I would not remove the leaves of young plants since the leaf is photosynthesizing even in spring and making the plant stronger. Once plants are established I will then begin removing the foliage each spring. Established plants won’t even notice the loss of their leaves.

Pests: Hellebores are usually problem-free in the garden. The older flowers and new growth can sometimes attract green aphids. These should be washed off with a jet of water from the hose or sprayed with an environmentally friendly insecticide like insecticidal soap or a formulation containing pyrethrins such as End All. Aphids secrete a sweet honeydew and if left too long it can become a site for fungus such as botrytis and sooty moulds. These can also be washed off or leaves can be removed. Aphids are also thought to be a vector for some viruses affecting hellebores. These viruses are not common but it’s best to remove aphids when they occur. Slugs will sometimes visit hellebore flowers. Use an environmentally friendly bait such as Safer’s Slug Bait during the flowering season.

That’s all you need to know about hellebores to be successful in your garden! Go forth and plant!

If you have any other questions, please email us.