Joyful cascade of winter blooms
Winter-flowering clematis bring welcome colour and finesse to the garden in the coldest months of the year
AS WINTER BEDS in, the garden becomes a beacon of hope during the daytime hours before the light begins to fade. Time spent here is precious, and plants that save their best for this cold and dark season are fondly welcomed. Forms of the winter-flowering climber Clematis cirrhosa become the gardener’s friend. Every evergreen is savoured this season, but those that flower too garner a special status, and these clematis are smothered in flowers during the cold months. Old walls and garden boundaries are elegantly decorated with their charming cascades of nodding, usually bell-shaped, blooms. Seeing these fine plants in their full winter glory creates a feeling as warm as a roaring log fire to the gardener.
Enduring presence
The flowers of Clematis cirrhosa reflect the generosity of the season in which they flower. The blooms are not large at up to 2½in (6.5cm) across, but when the plant is able to bask in sunshine, they are produced in abundance. As well as their mass appearance in winter, the flowers have longevity too, lasting from the beginning of winter until the early daffodils arrive in the garden to carry on the flowering baton in early spring. The flowers are also a vital source of nectar and pollen for any bees that are active in winter as a result of warm temperatures. As the flowers of Clematis cirrhosa fade for the last time, they are replaced with sweet, silky, spidery seedheads. These add an unusual feature to the garden in spring, when new life is everywhere, and the faded glory of flowers gone to seed are something of a novelty.
“Concealed were all thy beauties rare ‘Neath the dark umbrageous shade, But still to gain the loftiest spray, Thy weak stem its efforts made” Alexander Bathgate, ‘The Clematis’
Clematis cirrhosa is also a useful ‘backbone’ plant for the garden because some varieties are evergreen or semi-evergreen: they can naturally shed some leaves in summer. This makes them good ‘team-players’, keeping walls and fences covered all year while being happy to allow a summer clematis to grow alongside and steal the show in the warmer months. These are strong climbers, some capable of growing to 13ft (4m) or more. Young stems need tying to canes angled towards the wall or fence the plant is intended to cover. As the young growth shoots over the canes, it may also need gently tying to its main support with soft string to help it on its upward trajectory. As the stems age and firm up, they will wrap themselves around wire, trellis or pergola frames without help from the gardener.
The leaves of Clematis cirrhosa are a glossy dark green and tend to be smaller than those of the more familiar summer-flowering clematis, but they cover the plant well when plants are pruned regularly, so the structures that they scramble up can be obscured effectively. The finely cut, fern-like leaves of Clematis cirrhosa var. balearica are particularly attractive.
Clematis cirrhosa flowers on stems produced in the previous summer, so the time to prune is in spring, when flowering has finished and the risk of frost has gone. Routine annual pruning involves trimming back each stem that has outgrown its space, cutting back to a pair of healthy buds and also cutting out any dead or broken stems. If the plant has become bare, with all the growth and flowers at the top of the stem, it can be renovated by cutting back stems to 6in (15cm) above ground level. It may take the plant a while to settle down and flower again if a renovation prune is carried out. Allowing the plant to climb tall will also make it easier to
enjoy the flowers, because their nodding habit makes them difficult to view low down on the plant.
Warmth and protection
A European native, Clematis cirrhosa is common in Southern Europe and the Mediterranean, which gives a hint as to its preferred growing conditions. It should survive winter temperatures down to -10°C, but can be damaged by cold winds. Like most clematis that flower in summer, forms of Clematis cirrhosa will flower freely if grown in a sunny spot in the garden. However, because they need protection from wind, an open, exposed site in full sun is best avoided, and the ideal situation would be against a warm, sunny wall, where the soil stays dry in winter. They need soil that drains very well, because if it becomes waterlogged during winter, the plants may die. A mulch of well-rotted compost should be applied around the base of the plant after planting and again each spring. The plants naturally have a dormant period in summer, so it is not a problem if the soil around them dries out. During this time, the plant may look a little bit ‘ragged,’ but this is perfectly natural and not a problem that needs remedying with the application of lots of water.
Growing in containers
To grow these clematis in pots, the container should be at least 18in (45cm) in depth and width, and raised onto pot feet in winter to allow for good drainage. It is also important to ensure that the supports in the pot are sturdy if it is growing up a structure placed within the pot, otherwise the roots can be disturbed by strong winds. Placing an upturned 3in (8cm) pot over the drainage hole at the bottom of the container helps to prevent the hole from becoming clogged up with compost. A mix of John Innes compost with equal parts multi-purpose compost and a good handful of grit will improve drainage. The plant should be fed every fortnight in summer with a liquid tomato food to encourage a good flowering season in winter. The container should be positioned in a sheltered corner or, even better, the warmth of a house wall that can ideally be viewed from indoors.
Other winter-flowering clematis
Clematis armandii shares the need for shelter and free drainage of Clematis cirrhosa, and it begins to flower at the end of winter, continuing into spring, allowing for a long clematis season in the garden with just two plants. The flowers are a delight: creamy-white and star-shaped, with a distinct almond-like scent. Also an evergreen, it can reach ›
up to 16ft (5m) tall. Completely different to this and Clematis cirrhosa is the Nepalese native Clematis napaulensis. Needing more protection in winter, it is suited to a cool conservatory or being grown in a pot that can be moved somewhere above freezing if frost is forecast. The flowers are a real exotic delight: scented and appearing in clusters, with yellowy-green flowers bursting with purple stamens. It sheds its leaves in summer before putting on new growth in autumn, and reaches approximately 10ft (3m) in height.
For a winter clematis that looks like the ‘traditional’ summer forms, Clematis urophylla ‘Winter Beauty’ fits the bill. It has creamy, bell-shaped flowers reminiscent of Clematis cirrhosa, but with larger foliage that looks very similar to that of a summer-flowering form of clematis. It is another evergreen, growing to 12ft (3.7m) tall, and again needs a sunny spot away from strong winds in order to thrive.
Whether winter-flowering clematis are grown in pots or in the ground, when given protection from the worst of the elements, these special plants will thrive and bring a much-needed touch of elegance and finesse to the garden in winter. Mixed with spring-flowering clematis, such as Clematis montana, and then early and late-summer flowering varieties, there can be a clematis in flower in the garden almost all year round.