Black hellebore, stunning white flowers of Helleborus niger

Though it’s called black, the Helleborus niger flower is a pristine white color!

Black hellebore key facts

Botanical name – Helleborus niger
Common name – black hellebore, white hellebore, Christmas rose
Family – Ranunculaceae

Type – perennial grassy flower
Exposure – shade to part shade
Soil – rich, clayish, cool

Planting – fall or spring
Height – 1 foot (30 cm)
Foliage – evergreen

Blooming: mid-winter → early spring  –  Toxicity: very poisonous plant

Helleborus niger is also known as the black hellebore. It’s a strange common name for this evergreen perennial, because its flowers are either white or pink. The reason behind the name lies underground: its roots are black. This hellebore grows out from an underground rhizome that is short and thick. It breaks easily, and the outside peel of the root is black.

Spring foliage of this variety starts off bright emerald green, then slowly deepens to a deep jade color. Leaves are lobed, rather large, and lightly serrated (tooth-rimmed). January is when the blooming starts in earnest: magnificent white flowers appear, with waxy, round petals that slowly change to a pinkish hue with time.

Growing and planting black hellebore

Helleborus niger should be planted in fall or spring. This flowery grass loves growing in shaded or partly-shaded portions of the garden, where it’s cool and moist. It favors clay soil, loamy clay and clayish loam, as long as it stays cool and, preferably, rich. If the soil drains well, a thick layer of mulch should protect the plant against drought, since it locks moisture in.

Black hellebore is excellent for growing in pots.

• Remember to water often.
• Make sure excess water can drain out from underneath the pot.
• Don’t set the pot in full sun.
• It’s better to place it in a shaded portion of your terrace, balcony or courtyard.

Propagating black hellebore

Division

Dividing the clump is the easiest and most effective method to propagate Christmas rose.

However, it’s important to do this carefully, and only occasionally.

• Indeed, black hellebore doesn’t cope well with being transplanted.
• A good precaution is to try and keep as much soil as you can around the roots of the mother plant.
• Also, it’s best to only start dividing a hellebore clump once it’s already very well established, around 5 to 7 years after planting.

In spring, after the blooming, divide the clump with a single cut from a spade. Ensure proper watering during the summer that follows the division, this will help the wounded portion cope since it has less roots to rely on. You can also perform clump division for black hellebore at the end of fall. In that case, you probably won’t get any flowers during that first winter on the new plant.

Sowing

Recent seeds sprout easily. You might discover self-sowed seeds sprouting around the mother plant, under the protective leaf cover. Sow your black hellebore seeds in nursery pots, sometime between August and September. Cover them with half-an-inch of soil (1cm). Place your seedlings in a very moist, shaded part of the garden. Transplant young Christmas rose sprouts to their final growing spot in April of the following year.

Black-flowered hellebore

You might wonder whether there are any hellebore varieties with black flowers. These are almost always cultivars from another species, Helleborus orientalis, the Lenten rose.

Helleborus orientalis ‘Black’

The ‘Black’ lenten rose produces simple, cup-shaped flowers with a very dark color, nearly black. If you look closely, though, you’ll notice orange reflections on some petals. These ebony-black petals contrast elegantly with the bouquet of white stamens that appear at the heart of the flower.

Helleborus orientalis ‘Double Black’

The ‘Double Black’ lenten rose produces double flowers.

Its black color is slate blue with violet tinges and is identical to that of Helleborus Orientalis ‘Black’.

The blooming has several rows of thick petals, again with a heart of nearly white stamens.

Helleborus orientalis ‘Black Chocolate’

Another cultivar, the ‘Black Chocolate’, bears simple cup-shaped flowers with deep brown petals that also near on black. Again, they mark a stark contrast with the light-colored stamens. For this variety, the foliage also occasionally presents a deep violet color.

To learn more, read:

• Potted hellebore: 5 keys to make sure it grows
• Hellebore, flowers for the cold
• White hellebore: a magnificent perennial with white flowers
• Green hellebore: the green-flowered hellebore often found in shaded parks