Solitary clematis

Solitary clematis: how do you recognise it?

Habit

Loose clump 60–80 cm tall and about 60 cm across, with floppy stems that like to lean on neighbours.

Leaves

Simple, oval, opposite and stalkless; with smooth edges, hence the name integrifolia.

Flower

Nodding bells of 3–5 cm with four thick, twisted sepals that curl back at the tips, from June to August.

Colour

Indigo to violet blue with a cluster of cream stamens; there are also white and pink forms.

Fruit

Silvery, fluffy seed heads with long, hairy tails.

Roots

A sturdy rootstock with many roots; older plants are best not moved.

Flowering: June–August · Plants: March–April and September–October · Pruning: March

Why grow it?

• A clematis for the border, with no need for a trellis or wall.
• Flowers from June to August with graceful, nodding bells.
• The silvery seed heads stay attractive for weeks after flowering.
• Bees visit the flowers for pollen.
• Very hardy and long-lived, with simple pruning: cut everything back in March.

Solitary clematis: where does it grow best?

• Sun to partial shade; with its roots cool and its head in the sun it flowers best.
• Fertile, free-draining sandy, loamy or clay soil; chalk is no problem.
• Normal moisture: not too dry in summer and not waterlogged in winter.
• A spot between sturdy neighbours, such as low shrubs or perennials, that it can lean on.
• Allow 50–60 cm per plant.

Light

Sun and partial shade

Soil type

Sand, loam or clay

Acidity

Not fussy

Moisture

Normal

Size

0.7 m tall, 0.6 m wide

Hardiness

Hardy (to -35 °C)

Goes well with

• Roses: A classic pairing: the blue bells lean among the branches of low roses.
• Lady’s mantle: A soft, yellow-green foreground.
• Hardy geranium: Fills the base and props up the floppy stems a little.
• Yarrow: Flat yellow or white flower heads as a contrast with the nodding bells.

Solitary clematis: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or September–October.
2. Dig a generous hole and mix in compost; on heavy soil, loosen the subsoil as well.
3. Set the plant about 5 cm deeper than it was in the pot: it will form more buds below ground.
4. Leave 50–60 cm between plants and put in a support straight away, or plant next to a sturdy neighbour.
5. Water in well with a full can.
6. Mulch the base with compost to keep the roots cool.

Care

Watering

Regularly in dry spells in the first year; after that only in dry summers.

Feeding

In April, compost or an organic fertiliser for perennials.

Support

In April, put in a ring, a few birch twigs or a low obelisk; otherwise the stems fall apart.

Mulching

A layer of compost around the base keeps the roots cool.

Deadheading

Removing spent flowers can bring a few more; leave them and you get attractive seed heads.

Tip: Plant it next to a low shrub rose or a sturdy perennial: it will lean on it by itself and you won’t need a support.

Solitary clematis: when to prune it?

Pruning months: March.

When: In March, when the new buds at the base start to swell.

How:

• Cut all of last year’s stems back to just above the ground.
• Leave the young buds at the base untouched.
• After the first flush you can shorten spent stems for a second, smaller show.

Caution: Wear gloves when pruning: the sap can irritate the skin.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In spring, carefully divide an older clump with a sharp spade; each piece needs buds and plenty of roots.

Cuttings

In April–May, take young shoots from the base as cuttings and root them in moist cutting compost.

Seed

Sow fresh seed in autumn in a tray outdoors. It germinates slowly and unevenly, and seedlings may differ from the parent.

Solitary clematis: how does it get through the winter?

Hardy to −35 °C.

• Very hardy, to −35 °C: no protection is needed in Belgium.
• The stems die back; leave them until March so you know where the plant is.
• In a pot: choose a large, deep pot, keep it sheltered and do not let the compost dry out completely.

Diseases and pests

• Slugs: They eat the young shoots in spring. Pick them off in the evening or protect the plant with a collar.
• Powdery mildew: White powder on the leaves in dry late summers. Water enough, give plants space and cut off affected leaves.
• Flopping stems: Normal for this plant. Put in support in good time or grow it between sturdy neighbours.
• Clematis wilt: Rare in this herbaceous species. If a stem suddenly collapses, cut it back to healthy tissue; the plant usually regrows.

Through the year

• March: Cut all stems back to just above the ground. Planting.
• April: Put in support. Add compost. Watch for slugs.
• May: Guide the stems through the support. Take cuttings.
• June: Flowering begins.
• July: Full flower. Water in dry spells.
• August: Last flowers and first seed heads.
• September: Planting. Leave the seed heads standing.
• October: Planting. Sow fresh seed in a tray outdoors.
• November: The stems die back; leave them until March.

Edible and useful

Not edible. All parts of clematis are poisonous: when the plant is damaged it releases protoanemonin, an acrid substance also found in buttercups and anemones. On the skin the sap can cause redness, itching and blisters, especially in people who often prune with bare hands; in the mouth it causes a burning feeling, drooling, vomiting and stomach ache. The acrid, bitter taste puts off most people and animals, but keep small children, dogs, cats, rabbits and guinea pigs away from the plant and the clippings. Horses and other livestock can eat more of it if they reach a clematis over the fence or find the clippings: do not plant it along a field, and never throw the clippings into a field, pen or hutch. Wear gloves when pruning and tying in, and wash your hands afterwards. If any is swallowed, call a poison centre (in Belgium 070 245 245) or your doctor at once.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• Climbing clematis twine their leaf stalks around a support; this species has stalkless leaves and so cannot climb.
• The species has been grown in European gardens since the 16th century.
• The feathery tails on the seeds are elongated styles; they help the wind spread the seed.