Helleborus: Harbinger of Spring

The Perennial Plant Association recently named Helleborus xhybridus as the 2005 Perennial Plant of the Year.

The Perennial Plant of the Year program was initiated in 1990 to promote perennials that are suitable for a wide range of climates, require low maintenance, are easily propagated and display multiseasonal interest.

Helleborus xhybridus, or lenten rose, as it is commonly named, is not a rose at all. Instead, this harbinger of spring is an evergreen member of the Ranunculaceae, or Buttercup, family. Helleborus is a relatively small genus containing only 15 species of herbaceous perennial plants native to Turkey, Greece and the Caucasus region. Originally named Helleborus orientalis hybrids, lenten rose's scientific name was changed to Helleborus xhybridus to reflect the fact that species of Helleborus hybridize very readily. Since hybrids display superior flowering and color, they dominate the cultivars available today for use in the garden.

Hardy through zone 4, Helleborus has evergreen foliage and blooms in late-winter or early-spring, a time when many plants are still snow covered. Mature plants form a clump 18" to 24" in height and 24" to 30" in width, and may contain up to 50 flowers. Modern garden hybrids flower in a virtual rainbow of colors ranging from pure white to a dark plum color that borders on appearing black. In between these two extremes one can find cultivars that bear red, pink, yellow or spotted flowers. Flowers are nodding in appearance and either bell-shaped or cupped. They exhibit a very conspicuous cluster of yellow stamens in their center ringed by round petaloid sepals and come in semi-double to double form. Since the showy parts of the flower are sepals and not petals, they are extremely long-lived and often last for months. Unique and ornamental seed pods follow the appearance of the flowers adding further to its ornamental value as does its beautiful foliage.

Helleborus bears leather-like leaves palmately divided into seven to nine finely serrated segments whose evergreen nature and unique texture serve as an ideal backdrop in the shade garden for other plants.

Helleborus prefers a well-drained yet moistureretentive soil rich in organic matter. It is a relatively slow-growing plant with thick roots that do not like to be disturbed and will be slow to recover if moved or divided. Part-sun/shade to full shade is its preferred exposure at our latitude because of its preference for cooler temperatures. Further north, it will tolerate more sun. Helleborus is tough and requires only occasional watering once established. If its evergreen leaves become tattered during the course of a severe winter, simply remove them as new foliage appears in the spring. It should be noted that Helleborus leaves contain alkaloids that can cause dermatitis following long-term exposure to people with sensitive skin. The leaves, stems and roots of this plant are all considered to be poisonous. Members of this genus were said to have been used by ancient Greeks to poison the wells of their enemies.

Propagation of Helleborus can be accomplished either vegetatively or from seed. The latter is rather slow and might require four or five years to produce a blooming plant from seed. The diverse genetic makeup of Helleborus hybrids creates plants that produce a wide range of available colors, but they do not come true from seeds. Seedlings must be observed in flower before marketing as a particular color and for that reason nurseries offer a selection of mixed colors. Established clumps will produce an adequate supply of seedling for home propagation. Vegetative propagation is accomplished by dividing established clumps into single crowns but this is also slow since Helleborus does not like to be disturbed.

A stand-out in the late-winter and early spring garden, Helleborus is effective as a specimen plant (clump) or it can massed and used as a backdrop for other plants in borders or beds. Barrenwort, wood anemone and liverleaf represent spring-flowering plants that are good companion plants with Helleborus. Alternatively, Helleborus naturalizes nicely in woodland (shade) settings and tends to be long-lived when given proper care. Helleborus also can be used in mass to form an interesting evergreen ground cover. It is relatively free from insect and disease problems and is considered a low maintenance, easy-to-grow perennial.

If you have not yet grown Helleborus, this might be the year to do so since it should be readily available in nurseries and garden centers because of its recent designation as 2005 Perennial Plant of the Year. Be aware, however, that growing Helleborus can become addictive and most avid gardeners cannot stop at purchasing just one plant.

Credit: Perennial Plant Association

David Trinklein University of Missouri