Monday, December 3, 2012
Christmas Rose (Helleborus niger)
Robin Trott, University of Minnesota Extension Educator
I know the growing season is officially over when we make our annual trek to the Association of Specialty Cut Flower Growers conference. This time we travelled to Tacoma, WA, and had the great pleasure of visiting growers in the Skagit Valley, north of Seattle. This year's particular delight was visiting Skagit Gardens and beholding their greenhouses filled with hellebores.
This alpine plant grows native at high elevations and produces large white flowers that turn a blushy pink as they age. Until recently, these perennial plants (hardiness zone 4-9 depending on species) were the sole domain of rare plant collectors, with prices way beyond the pocket book of average consumers. With the breeding programs developed at Skagit and other wholesale nurseries, a variety of cultivars are available at garden centers nationwide.
Hellebores are anatomically separated into 2 groups, "caulescent" and "acaulescent". Caulescent hellebores are those with above-ground stems (Figure 1). Acaulescent plants are those where the flowers are born on their own stalk with no leaves, and the leaves have their own stalk (Figure 2). Caulescent varieties are popular for use by florists in dramatic arrangements.
The Christmas rose is the best known and certainly the showiest of the species hellebores (Photo 3).
Easier to grow than the ever popular "Poinsettia", plant breeders like Skagit are hoping to promote this flower as the new and improved holiday potted plant which can later be transplanted in perennial beds to bring joy year after year.
If you select a hellebore as a holiday accent this year, keep these horticultural tips in mind:
For indoors care, keep your plant in a bright cool location, away from any heat source. (Hellebores will bloom through snow, they like it cold!) Keep the soil moist; don't let the plant dry out! Don't worry if your hellebore gradually yellows, this is natural. If you are concerned, move it to a cooler location. Plant your hellebore outside in partial to full shade as soon as the ground has thawed. Protect your transplant from weather extremes until it has become established.
Once transplanted, mulch your hellebore to keep the soil cool and moist throughout the summer months. Make sure you have selected a site that is protected from desiccating winds. The new breeding of these beauties has made them disease and insect resistant. Once established, they require minimum additional care. Deer don't touch hellebores, which is an added bonus to this delightful flowering plant.
Although each variety holds it blooms for a lengthy period, during which time the flowers turn from pure white to pinkish green, you can increase your bloom time by selecting several different cultivars.
Jacob: the traditional "Christmas Rose" will bloom as soon as the frost begins to leave the ground in the spring. It is a compact plant (9-12"x 13" spread) with pure white slightly fragrant blossoms atop burgundy stems.
Josef Lemper: another Helleborus niger is a taller (15-18"x 21"spread) early bloomer.
'Winter's Bliss': Is a later blooming variety whose large white blossoms fade to deep pink with age. It grows 15-18" with a 24" spread.
Joshua is a 12-15" early blooming variety with a 17" spread. Its slightly fragrant white blooms age to light green. Its foliage is glossy dark green and works well as filler in your springtime arrangements.
Silvermoon: (15-18"x21") has creamy blossoms tinged in pink atop rose colored stems.
This is just a small sampling of varieties that are hardy to USDA Zone 4, and thrive in Minnesota Gardens. Check with your local garden center this spring for varietal availability.