Clematis

For a list of different varieties of clematis – click here. 

Clematis are generally grown on a trellis by the house. Another method is over an arbor, arch or supported by a shrub or upright evergreen. Clematis will grow in full sun to part shade. More importantly, their roots must be kept cool so grow them either in the shade of a small shrub such as potentilla, or with the ground mulched with two inches of bark or peat.

How to Plant

1. Dig a large hole, about 45cm x 45cm x 45cm (45cm = 18”)
2. Add roughly 2 buckets of peat moss to the top soil along with compost or composted manure and a handful of bone meal. Make sure to mix all of the new ingredients very well with the existing topsoil. Remember any extra effort put into soil preparation now will pay back many times over in the years to come.
3. Set the Clematis into the planting hole so 5-10 cm (2-4”) of the stem above where the roots start will be below ground level.
4. Fill the hole back in with your soil mix.
5. Soak well with ½ strength fertilizer like Plant Prod 15-30-15. Let water soak in and then finish the planting.
6. Remove support stick and prune back to a set of buds at a height of 30cm (12”) above ground level. Pruning stimulates good root growth.

Types of clematis (by colour)

Purple Clematis

C. Guiding star – Medium sized dark royal purple, pointed sepals with reddish-purple streaks which tend to tone in with the overall colour. Free flowering vine of medium vigour, requiring moderate pruning, can be cut back to 60 to 120 cm (2-3 ft.), if vines become overgrown.

C. Gypsy Queen –  Large velvety violet-purple, somewhat like Jackmanii, except larger flowers. Summer blooming with vigorous growth habit, requires pruning back to 50 to 100cm (20-40 in).

C. Jackmanii – Deep velvet purple. Our strain of this old favorite is similar to the European Clone “JACKMANII SUPERBA”. This clematis makes vigorous rapid spring growth and commences blooming on the new growth the first week of July in the Niagara area. Can be pruned hard each year by cutting back to 30 to 90 cm (12 to 36 in). This is our hardiest and most popular variety.

C. President – Large flowering deep purple-blue with reddish-purple stamens, blooms are slightly cupped. This beautiful flower is quite vigorous when established and requires moderate pruning. Can be cut back to 60 to 120 cm (24-48 in), if vines become overgrown.

Blue Clematis

C. Elsa Spath – Rich lavender-blue, extra large flowers with pointed sepals and dark stamens. Prune lightly to shape the overall appearance during the first two years. After the plant is well established, prune each year by cutting back to 60 to 120 cm (24-48 in).

C. Lady Betty Balfour – Dark blue, with attractive creamy-white stamens, vigorous growing and very hardy. This superb variety requires hard pruning every March by cutting it back to 60 – 120 cm (24-48 in). This is a late flowering variety requiring a sunny location for a profusion of blooms.

C. Lawsoniana – Lavender-blue with a rosy tint, long pointed sepals, pale brown stamens, large flowers. Prune lightly in early spring. 

C. Lord Neville – Dark blue large flowers with purple stamens and pointed wavy-edge sepals. Only limited pruning is required to shape the overall appearance.

C. Mrs Cholmodley – Large light blue sepals with brown stamens. Large open type flowers and prolific long lasting blooms. Prune lightly when plant becomes overgrown.

 C. Perle d’azur – Sky blue with green stamens, vigorous growth habit, free flowering with masses of medium sized flowers. Prune lightly when plant becomes overgrown.

C. Ramona – Very popular, large satiny lavender-blue, with dark stamens and rounded sepals, also known as Hybrid Seiboldi. Although this old favourite is quite vigorous, it requires little pruning. The plants need to be pruned only enough o improve the overall shape.

C. Tillicum – Very large, delicate bile with deep purple stamens. No pruning necessary unless plant becomes overgrown.

C. Vyvyan Pennell – Double violet blue flowers. Flowering in June on the previous year’s growth with sepals around the outside and a large rosette in the center. (Flowers resemble Peonies). Late in the year, flowers are mostly single, some semi-double on the new growth. No pruning required.

C. William Kennett – Deep lavender with dark purple stamens, a handsome variety, large flowers, pruning is optional, however, cutting back lightly is usually beneficial.

Red Clematis

 C. Crimson King – A good red clematis with brown stamens, with a little more mauve tone than Ernest Markham. Flowers are medium in size and fairly early. Require only limited pruning to shape the overall appearance.

C. Ernest Markham – Large flowering, glowing petunia-red with golden stamens. The best red clematis for southern Ontario. This vigorous growing clematis can be cut back to 50 to 100 cm (20-40 in) in March, and it will produce masses of large flowers in late summer. If the old wood is not cut back, it will produce somewhat smaller flowers on the old wood in late spring. Ernest Markham prefers a sunny location, with the roots shaded and mulched.

C. Rouge Cardinal – Glowing crimson with brown stamens, medium sized flowers. Prune hard in early spring by cutting back to 50 to 100 cm (20-40 in).

C. Ville de Lyon – An abundance of carmine red blooms shading to deep crimson on the outer edges of the sepals; producing a profusion of medium-sized flowers. This very hardy, vigorous variety blooms in July and it can be pruned back to 30 to 90 cm (12-36 in) each year in March.

Pink Clematis

C. Comtesse de Bouchaud – Gracefully curved sepals ranging in tone from satin rose to mauve-pink with yellow stamens; medium-sized flowers bloom in great profusion in July. This vigorous clematis requires pruning back to 30 to 90 cm (12-36 in).

C. Mme Baron Veillard – A profusion of medium-sized lilac-rose flowers with yellow stamens blooming during late July and August. This vigorous growing clematis requires pruning back to 30 to 90 cm (12-36 in).

C. Pink Chiffon – Medium-sized pink flowers with burgundy stamens and pointed sepals. This free-flowering variety is also known as Hagley Hybrid. Limited pruning is sufficient. It can be cut back to 60 to 120 cm (24-48 in) when vines become overgrown.

Mauve Varieties with Bars

C. Barbara Jackman – A soft mauve with a violet-crimson bar and creamy stamens. This plant only needs enough pruning to improve overall shape.

C. Bees Jubilee – A deep mauve-pink with a deep carmine bar, often described as an improved Nelly Moser. This Variety flowers both on the old and new growth; needs pruning only to shape the overall appearance.

C. Capitan Thuilleaux – Broad strawberry-pink bars on a cream background; pointed sepals, golden brown stamens, medium sized flowers, (introduced by Fish’s in 1967). Prune in early spring by cutting back thin stems and removing dead wood.

C. C.W. Dowman – Pale pink with carmine bar and golden stamens. Medium growth habit. No pruning required.

C. Dr. Rupple – Deep carmine-pink bars upon light pink sepals, golden stamens, medium-large flowers, (introduced by Fish’s in 1975). Prune lightly in early spring.

C. Mrs. N. Thompson – Deep violet with a vivid scarlet bar and reddish stamens. Medium type growth habit which should be pruned lightly.

C. Nelly Moser – Large pale mauve with carmine bars; flowers are produced in amazing profusion. This variety tends to fade in full sun, but does exceptionally well in partial shade, such as an eastern exposure. Flowers both on the old and new growth, needs limited pruning to shape the overall appearance.

C. Sir Garnet Wolseley – Mauve-blue sepals with a purple bar. Early flowering, medium sized blooms have red-brown stamens. Prune lightly to shape plant.

White Clematis

C. Duchess of Edinburgh – Double white rosette-shaped flowers blooming in late spring followed by semi-double flowers in late summer on the new growth. Needs only limited pruning to shape the overall appearance.

C. Henryi – Unusually large white flowers with pointed sepals and dark stamens, growing often to 30 cm (8 in) in diameter. Henryi is a vigorous plant remaining bushy. Prune lightly to shape overall appearance.

C. Huldine – Medium-sized pearl-white flowers with a slight showing of mauve bars on the underside of the sepals. This very strong vigorous variety produces a mass profusion of flowers. It should be pruned every year by cutting back to 30 to 90 cm (12-36 in).

C. Marie Boisselot –(syn. Madame-La Coulte) – Pure white with yellow stamens, a beautiful flower with overlapping sepals, large flowering; prune lightly in early spring.

Species and Small Flowering Clematis

Clematis Alpina (Zones 2-9)

The alpine group of Clematis are hardy spring-blooming vines which originated in Siberia/ They flower on the old wood of the previous year’s growth and consist of masses of single bell-shaped flowers. This sub-zero group of Clematis grows to a height of 1.5 to 2.5 m (5-8 ft) requires no pruning and has attractive fluffy seed heads. Deep blue, single lantern-shaped flowers.

C. Alpina ‘Pamela Jackman’ – Deep blue, single lantern shaped flowers.
C. Alpina ‘Ruby Wine’ –  Red, single lantern-shaped flowers.
C. Alpina ‘Frances Rivis’ – Mid-blue lantern-shaped flowers with a beautiful centre of white petaloid-stamens.

Clematis Macropetala (Zones 3-9)

The macropetala group of Clematis are hardy spring-blooming vines which originated in Siberia. They flower on the old wood of the previous year’s growth and consist of semi-double flowers. This sub-zero group of Clematis grows to a height of 2 to 3 m (8-10 ft), requires no pruning and has attractive fluffy seed heads, sometimes called “Downy Clematis”.

C. Macropetala ‘Blue Bird’ – Large, light purple-blue, semi-double flowers. Originated in Manitoba by “Dr. Skinner”.

C. Macropetala ‘Maidwell Hall’ – Deep blue semi-double bell type nodding flowers.

C. Macropetala ‘Markham’s Pink’ – Light pink with cream stamens, single narrow pointed sepals, bell type nodding flowers.

C. Macropetala “Markhamii”- Lavender-pink with greenish-white stamens double nodding flowers.

C. Macropetala ‘Rosy O’Grady’ – Beautiful pink star-shaped flowers, very prolific bloomer.

C. Macropetala ‘White Swan’ – White flowers, originated in Manitoba by “Dr. Skinner”.

Clematis Paniculata (Zones 2 – 9)

Masses of sweetly scented cream coloured small flowers with prominently white stamens, blooming in late Aug. and early Sept. often called “SWEET AUTUMN CLEMATIS”. The flowers are followed by interesting sliver-white plumes of the seed heads. This variety is hardy and the overall appearance effective. The vines are very vigorous growing to a height of 3-6 m and require a minimum of 6 hours sunlight to obtain a profusion of flowers.

This species requires little or no pruning if you wish to cover a large area. To contain the plant, cut it back to 60 to 120 cm (24-48 in) in March.

Clematis Tangutica (Zones 2-9)

Yellow flowering species. A vigorous variety with masses of bright yellow lantern-shape flowers on vines 2 to 4 m (7-12 ft). The flowers are followed by beautiful silver-white plumes o the seed head which hang onto the vine all through the late summer, fall and winter. This variety is very hardy and can be pruned lightly in early spring or immediately after flowering, if the vines need to be shaped to make the overall appearances effective. Tangutica requires 2 years or more to become well established.