Plant of the Month: February

Helleborus hybridus Family: Ranunculaceae Vital statistics Height and spread: Up to 45cm (18in) high and wide Form: Herbaceous perennial Soil: Heavy, neutral to alkaline soil Aspect: Dappled shade Hardiness: Hardy throughout the British Isles

Helleborus hybridus is naturalised at Hyde Hall in Hermiones' Garden, a shaded woodland dell, and in the adjacent Woodland Garden. The drifts of hellebores thrive under the woodland canopy and begin to flower as shrubs such as Camellia open, and as the spring bulbs like Galanthus nivalis and Narcissus bulbocodium emerge.

Hellebores

Helleborus is a small genus containing 15 species of herbaceous perennials found mainly in scrub and woodland on chalk or limestone soils. Most species are European, though hellebores can be found as far afield as western Asia.

Helleborus foetidus and H. viridis are both British natives occurring on the chalk-hills of southern England in woods and scrub, often forming quite large colonies.

The true wild hellebore species are rarely grown in gardens as hellebores hybridise very easily and the hybrids are much better garden plants with improved form, flowering and flower colour. Most of the hellebores grown in gardens are hybrids involving Helleborus orientalis, crossed with H. cyclophyllus and H. ordorus to give yellow flowers, H. multifidus subsp. bocconei to give green flowers and with H. torquatus to produce deep purple colours.

Other hellebores have also been used to create garden hybrids including Helleborus argutifolius and H. lividus. These species hybridise readily to produce hybrids named Helleborus x sternii after Sir Frederick Stern, one of the first exhibitors of this hybrid at an RHS Show.

Hellebores have also been associated with medicine for over 2200 years. In southern England the powdered leaves of Helleborus foetidus were given to children troubled with worms, though it was described as 'a violent remedy'. We now know that hellebores contain poisonous cardiac glycosides that have a burning taste and can also cause unpleasant dermatitis if the sap gets onto the skin.

Helleborus hybridus

Helleborus hybridus is the name given to a group of variable, clump forming, perennial hybrids of H. orientalis and other species. The name has only recently been accepted and many labels in the gardens identify plants as Helleborus orientalis.

Depending on the hybrid, the leathery, mid to dark green leaves may be deciduous or overwintering. From mid-winter to mid-spring saucer shaped, pendent flowers are borne on stout stems, with colours ranging from white, yellow and green to pink and purple.

Cultivation

Helleborus hybridus will tolerate all but very poorly drained or dry soils, but the optimum conditions for cultivation are a heavy, neutral to alkaline soil and dappled shade.

Plant in autumn and leave undisturbed as the fleshy roots transplant badly and may take several years to re-establish before flowering again. The plants will benefit from the incorporation of organic matter at planting and an annual mulching with leafmould in autumn.

All hellebores are susceptible to leaf spot which appears as large brown lesions on young foliage in the early part of the year. If severe, the lesions will spread to the flowering stems and can occasionally cause the collapse of the entire plant.

Helleborus hybridus cultivars are also susceptible to hellebore black death, the cause is unknown at present but the symptoms appear as black streaking and mottling of the tissues along or between the leaf veins. To reduce the risk of spread, infected plants should be dug up and destroyed immediately.

Propagation

Seed can be collected and sown when fresh but in most cases will not come true to the original parent. It is advisable to wear gloves when extracting the seeds.

Division will ensure that all plants are the same. Divide plants either in spring or late summer/early autumn, taking great care of the fragile fleshy roots otherwise flowering will be affected for several years while the plant re-establishes.

More information

Hellebores

Further reading

McLewin, W & Mathew, B. 1995. Hellebores: 1. The genus Helleborus. The New Plantsman 2(2):112-122.

McLewin, W & Mathew, B. 1998. Hellebores: 6. Helleborus orientalis & H. x hybridus. The New Plantsman 5(2): 117-124.