Anticipating spring can be a long, tedious wait. Often the cherry blossoms are blooming in Vancouver, while here in Southern Ontario, we are still contemplating whether we should put our parkas away for good. As you patiently bide your time until you can head outdoors into the garden, consider the spring-blooming plants you may want to add to your must-have list, such as hellebores.
I finally decided to add a hellebore to my garden in 2015. I thought the perfect person to consult for growing advice would be Gary Lewis, the owner of Phoenix Perennials, a nursery and mail-order company that ships 63 varieties of hellebores across Canada. Gary himself has 185 hellebores in his garden and says he’s still collecting. In fact, Gary is so passionate about the plant, he hosts an annual Hellebore Hurrah event.
What are the best growing conditions for hellebores?
Hellebores perform best in medium light levels—not too bright and not too dark. Though they are tolerant of both shade (especially in hot summer climates) and full sun (especially in cool summer climates or with even soil moisture), hellebores perform best in part sun to part shade. In these conditions, they will bulk up the fastest and bloom the most. Hellebores have a sizeable root system and prefer rich, deep, evenly moist soils. They do show a little drought tolerance once established. In their natural habitats they often grow in alkaline soils. On the West Coast, our soils are somewhat acidic and they grow well here. Hellebores seem tolerant of a range of pH though some gardeners who garden with acidic soils will sprinkle lime around their hellebores.
When is the best time to plant a hellebore?
Spring and fall are the best times for planting, though spring is probably best for the colder zones 4 through 6. Hellebores put on active growth in both spring and fall. When temperatures climb in the summers, hellebores stop growing and wait for cooling conditions to arrive.
If I purchase a hellebore in February as a houseplant, when can I bring it outside?
Hellebores are quite hardy. Helleborus niger should be hardy down to zone 4. Helleborus x hybridus and the stemmed hybrids such as Helleborus x sternii, Helleborus x ericsmithii, Helleborus x ballardiae, Helleborus x nigercors should be hardy to zone 5, though possibly colder with good snow cover and protected microclimates. That being said, you can’t shock a hellebore by taking it from warm conditions straight out to minus 15! If you got a Christmas rose for seasonal decoration or picked up other hellebores in the winter they should be kept in your coolest room with good light. They can be planted outside when temperatures remain above freezing in the spring. But before planting, you should gradually get the plant used to the cold by placing the pot outside for increasing periods over a one- to two-week timeframe.
Are there any hellebore pests or diseases one should look out for?
Hellebores are relatively carefree though their old flowers and new foliage sometimes come under attack by green aphids. These can be jetted off with water or sprayed with insecticidal soap. There are a few different fungal leaf diseases that can affect hellebores but these are uncommon. Usually they occur on hellebores planted in really shady conditions in really moist soils. Simply moving the hellebore to a brighter position usually clears up the problem.
What is your all-time favorite hellebore?
Helleborus ‘Rosemary’ is one of the best hellebores of all time. She is a rare cross that has only been made a couple times in the history of horticulture between the Lenten rose, Helleborus x hybridus, and the Christmas rose, Helleborus niger. These plants come from the acaulescent and caulescent groups of hellebores, respectively, and are not closely related, hence the difficulty in crossing them. ‘Rosemary’ has incredibly unique pale pink flowers with faint striping. The flowers darken with age through light salmon tones through to deep rich salmon colors. And it will bloom for three months or more starting after the Christmas roses, but up to one month before the Lenten roses.
Helleborus ‘Rosemary’ has been available in limited numbers for about three years so I still consider it to be a new hellebore well worth much attention.
All photos (besides the main image and the pin) provided by Phoenix Perennials.