Gareth Carter: Winter roses produce spectacular display

Helleborus Sophie's Delight.

Flowering plants in the wintertime bring so much cheer. We are right in the middle of winter and there is some great colour about if you look.

It is a good time to identify winter-flowering plants and which ones you can add to your garden — early magnolias are out and many camellias are putting on a great show. Daphnes, too, are starting to flower as well as many grevilleas with their flowers providing nectar for birds.

The focus of this column is the helleborus. Commonly known as lenten or winter roses, these cold-weather beauties produce a spectacular display in the wind, rain, frost and any other conditions that generally make resting by the fireplace seem desirable.

The winter rose is a highly valued plant offering colour at this time of year when it can be hard to find it in the garden. The blooms can be enjoyed indoors where they will last for up to three weeks as a cut flower. Some early-blooming varieties start flowering from late May and run into late July; other varieties start during July and will run into late August or even September. In the Northern Hemisphere, this coincides with the Christian festival of Lent, hence the name lenten rose.

Traditionally, hellebores were mostly white and pink, with shades in between. No longer is the colour range restricted. The winter rose has experienced intense, focused breeding and selecting of varieties in recent years. The result has been an abundance of new, highly desirable flower forms, colour shades and shapes.

The colours now range from the traditional white through the shades of pink to dark, black flowers. Also, there are green-flowered hybrids, yellows, apricots and all the combinations of the above in “picotee” (spotted) colour formations. There are also double-flowered hybrids in an exceptional colour range.

A few varieties highly worthy of mention:

Ice N Roses Red has blooms in a vivid red. These deeply coloured blooms stand relatively upright showing their faces. Grows about 40cm high by 60cm wide. (ref. Kiwi Gold).

Sophie’s Delight combines pure white and deep mulberry on a simple and elegant bloom held above its evergreen foliage. (ref. Livingfashion).

Conny has a unique speckled pattern of contrasting purple-red speckles on silvery white petals. The flowers are profuse and are about 5cm across. Bred in Germany, this strong, healthy grower will form an evergreen, small-spreading cover of about 40cm high by 60cm wide.

Tutu has semi-double flowers that are a dusky pink colour and show lovely speckling. Bred for its superior flowers, it blooms in August and September.

Molly’s White has white flowers that are flushed lime green. An attractive plant and flower with cup-shaped blooms.

Helleborus are shade-loving plants, preferring good drainage. They are ideal for growing under trees and along the shady side of a house or fence.

Most of the helleborus species enjoy humus-rich free-draining soil. They occur naturally in the deciduous forest and meadows of Eastern Europe. This situation provides lovely organic material in the form of leaf mould and built-in drainage provided by the tree roots. You can mimic this situation in your own patch by planting helleborus under trees and the addition of Yates peat moss.

Helleborus also enjoy soil of higher pH, lime rather than acidic soils, although as long as there is a relatively neutral pH you can grow hellebores with rhododendrons.

In areas that have heavy clays, one needs to be a lot more careful to provide the necessary drainage. Planting in raised beds is one helpful solution or planting under trees is another.

The method of planting right into the base of deciduous trees works on the principle of the tree taking up excessive moisture immediately under it, therefore providing suitable drainage. You need to be a little careful with the likes of conifers, which may block out moisture completely, because the hellebores do need some moisture.

Helleborus enjoy being mulched; this has many benefits — it keeps the plant moist and cool over the summer, is a great source of organic material and is also really good at keeping the weeds down. The best time to apply mulch is generally in the spring at the time when the old leaves are cut off just as the flower buds are appearing.

Cutting the leaves off the Helleborus x orientalis hybrids is beneficial but not absolutely necessary. The flowers will come through the old leaves perfectly well but the plants look tidier with the old and dying leaves removed. You can leave on any good-looking healthy ones. The clearing of the old leaves does help display the flowers better and also provides a good airflow around the plant’s corm to reduce the risk of fungal disease. Don’t cut the leaves off the other species, just Helleborus x orientalis.

Diseases in helleborus are not a major because the plants are very resilient. Helleborus leaves are poisonous to animals, although they will not eat them unless under extreme pressure. Some people have them growing in paddocks and the sheep and cattle will graze right around them without touching the leaves. Aphids can attack during summer — they don’t care if they are poisonous or not. The use of Yates Mavrik proves effective against these pests.

Helleborus do not need much in the way of fertiliser. If you mulch once a year, you can rely on that to provide nutrients. A top-dress with Novatec fertiliser is beneficial, but don’t be too heavy-handed. Dolomite Lime is also beneficial to add calcium.

Helleborus will tolerate a dry site far better than a wet one. It doesn’t really matter how much rain, hail and snow you get as long as the plant doesn’t sit in wet, boggy soil for too long. Free drainage is paramount. You can bring a helleborus back from death’s door from being too dry but it won’t come back from being too wet.

For more gardening information go to www.springvalegardencentre.co.nz

Gareth Carter is general manager of Springvale Garden Centre.