Evergreen and winter-flowering clematis: C. cirrhosa, C. armandii and more

Most clematis are deciduous summer climbers, but a small group keeps its leaves all year or flowers when little else does. Grown well, they bring scent in early spring, flowers in the depths of winter and a green screen across a fence in January.

What they have in common

Nearly all the clematis in this article belong to pruning group 1: they flower on growth made the previous year, so they need little or no winter pruning. They are also less hardy than the familiar summer types. The RHS rates C. cirrhosa, C. armandii and C. × cartmanii 'Avalanche' as H4, meaning hardy through most of the UK (roughly -10 to -5°C), and recommends that evergreen clematis be given a sheltered position, protected from cold winds.

Clematis cirrhosa: flowers in winter

C. cirrhosa is an evergreen species from the Mediterranean region that flowers from late winter into early spring, with pale yellow to cream bell-shaped flowers, sometimes flecked red inside. The RHS gives a height of 2.5–4m and recommends a sheltered, sunny south- or west-facing position.

Cultivars to look for

• 'Freckles' (C. cirrhosa var. purpurascens): creamy flowers heavily speckled with red inside. RHS Award of Garden Merit (AGM).
• 'Wisley Cream': plain, creamy flowers. RHS AGM.
• 'Jingle Bells': pale yellow to creamy-white bells which, according to the RHS, form on the previous year's growth from late autumn to early spring.

Plant C. cirrhosa where you will see it from a window or path, because it flowers when few people linger in the garden. The RHS marks 'Freckles' and 'Wisley Cream' as plants for pollinators, a welcome source of food for insects on mild winter days.

Clematis armandii: scent in spring

C. armandii is a vigorous evergreen climber from China with leathery, glossy leaves up to 15cm long and clusters of fragrant, creamy-white flowers in early to mid spring. The RHS gives a height of 4–8m and notes that it can exceed 8m if not pruned, so it needs space: a long fence, a pergola or a large wall. To enjoy its scent at its best, the RHS recommends a sunny, sheltered spot. Named forms include 'Apple Blossom', with pink-tinged flowers, which holds the AGM.

Its large leaves can be scorched by hard frosts and cold winds, so give it the warmest, most sheltered wall you have. Like many evergreens, it sheds some older leaves through the year.

New Zealand hybrids: 'Avalanche'

C. × cartmanii 'Avalanche' is a hybrid of New Zealand species, with finely divided, glossy evergreen leaves and sprays of pure white flowers about 4cm across in early to mid spring. It reaches 2.5–4m in the ground. The RHS notes that it can be grown in a container in a cold greenhouse or conservatory, which is a good way to grow it in colder areas; our guide to clematis for containers explains how.

Other winter and early spring clematis

The RHS also lists C. napaulensis (the Nepal clematis), C. urophylla 'Winter Beauty' and 'Early Sensation' among its winter- and spring-flowering clematis. These are less widely grown; check the hardiness of each before planting, and give them a sheltered site.

The deciduous spring clematis, such as C. alpina, C. macropetala and C. montana, belong to the same pruning group and are considerably hardier. AGM alpina types such as 'Frances Rivis' are rated H6, hardy throughout the UK. In a cold or exposed garden, they are the safer choice for early colour.

Where to plant

• Shelter first: a south- or west-facing wall or fence, out of cold winds, is ideal for C. cirrhosa and C. armandii. In colder northern or inland gardens, a warm wall can make the difference between success and repeated frost damage.
• Space: C. armandii in particular needs a large support; it is not a plant for a single trellis panel.
• Depth: unlike large-flowered hybrids, evergreen and winter-flowering types should be planted with the top of the rootball just below soil level, according to the RHS. See how to plant a clematis.
• Roots: they still like cool, moist, well-drained soil. The RHS advises against poor, waterlogged or heavy clay soils, and suggests protecting plants from excessive summer dryness.

Protecting them in a cold spell

Established plants on a sheltered wall usually come through a normal British winter, but young plants are more vulnerable. During a severe cold spell, a double layer of horticultural fleece over the top growth, removed once temperatures rise, can protect leaves and flower buds. An autumn mulch over the root area helps too, and the roots matter most: even if the top growth is damaged, a plant with healthy roots can regrow. Plants in pots are more exposed, because roots in a container freeze more easily than roots in the ground, so move pots against the house wall or into a cold greenhouse.

Pruning

As group 1 clematis, these need little routine pruning. If they outgrow their space, prune straight after flowering, so the new growth has time to mature and flower the following year. The British Clematis Society advises leaving the new green stems of winter-flowering types alone, because they carry the flowers, and tidying brown growth only once fresh green growth appears. Our guide to clematis pruning groups has more detail.

An overgrown C. armandii can become a tangle of bare stems with leaves only at the top. Thinning a few of the oldest stems after flowering is gentler than cutting everything back hard, which is likely to cost you flowers. If drastic renovation is needed, the RHS suggests cutting group 1 stems to about 15cm after flowering, and not repeating this within three years.

Using them in garden design

• Use C. armandii to screen a fence, shed or oil tank with year-round leaves.
• Plant C. cirrhosa near a door or window so its winter flowers are seen.
• Combine an evergreen clematis with a summer-flowering group 3 clematis on a large support for a second season of flowers, keeping in mind that they need pruning at different times.