Clematis - Notes from talk

Ranunculaceae

 

Includes 48 species mainly herbaceous
Ranunculus
Helleborus
Anemone
Hepatica
Aquilegia
Delphinium
Nigella
Caltha

 

Clematis

 

Queen of all vines
Klema in greek means “vine branch”
Genus includes in excess of 1000 species
More than 300 species recorded
Over 120 species currently in cultivation
By 1872 more than 200 species recorded

 

History

 

1569 Clematis viticella from Europe introduced to Britain
C. integrifolia, C. cirrhosa, C. flammula from Europe in 1596
C. recta 1597
American species in the early 1700’s
C. orientalis from Asia 1731
Later part of 18c many Chinese introductions

 

Distribution

 

1569 Clematis viticella from Europe introduced to Britain
C. integrifolia, C. cirrhosa, C. flammula from Europe in 1596
C. recta 1597
American species in the early 1700’s
C. orientalis from Asia 1731
Later part of 18c many Chinese introductions

 

Hybrid Clematis

 

1835 C. x viticella x C. integrifolia = C. ‘Hendersoni’
1860-1890 Glorious thirty years breeding
1858 George Jackman crossed C. ‘Hendersoni’ with C. lanuinosa = C. ‘Jackmanii’
First recordings of Clematis wilt

 

Early Clematis Breeders

 

Jackman’s of Woking 1810
Thomas Crisp & Son Tunbridge Wells
Charles Noble of Sunningdale
Victor Lemoine of Nancy
Francisque Morel of Lyon

 

20th Century Clematis Breeders

 

William Robinson & Ernest Markham of Gravetye Manor Sussex
Clematis tangutica ‘Gravetye’
Clematis texensis ‘Gravetye Beauty’
Clematis ‘Huldine’
Robinson published ‘The Virgins Bower’
Markham was head gardener (Percy Picton)
Pennell's of Lincoln 1780 - 48 large clematis20th Century Species

 

20th Century Species introduced

 

Clematis armandii
Clematis chrysocroma
Clematis montana var rubens
Clematis rehderiana
Clematis wuxiensis 2016 China

 

The Clematis Family

 

Deciduous or Evergreen
Woody, semi-woody or herbaceous
Leaves generally opposite
Petiole or leaf stalk twists or coils for support
Bisexual or unisexual
Tepals not petals
Male stamens, numerous, can be petal like
Pistils long and hairy
Seed-heads often plume like and persistent

 

Clematis Groups

 

Small flowered
Early flowered
Evergreen
Alpina
Macropetala
Montana
Late Flowered
Herbaceous and sub shrubs
Viticellas
Tanguticas
Texensis-Viorna
Other late species

 

Clematis Naturally

 

In the wild
According to species
Alpine species
Forest species
In the garden
Copying the wild
No visual supports
Equal vigour of host and clematis

Clematis on Walls and Fences

 

Suitable but invisible support
Access for maintenance
Some groups will flower in next door gdn
Legal position
Dry zones against walls and under eaves

 

Clematis on Arches, Pergolas

 

Suitable support
Colour scheme for all plantings
Access to carry out pruning
Clematis for sun or shade?
Equal vigour to look balanced

 

Clematis over other plants

 

As at Burford House Gardens Tenbury Wells many years ago
John Massey’s Garden at Ashwood
Clematis can be grown over small shrubs or conifers
Colour combinations with flowers or foliage

 

Clematis and Roses

 

Simultaneous colour display
Extend flowering season
Equal vigour
Pruning methods compatible
Shade for roots of ClematisClematis on Clematis

 

Clematis on Clematis

 

Contrasting colours
Different flower shape
Flowering at the same time
Pruned by same method

 

Herbaceous Clematis

 

Deciduous
Cut down in autumn
Slug control
Some do not have tendrils
Encase in frame
Useful addition to herbaceous border

 

Clematis as ground cover

 

As occurs in the wild, Clematis alpina
Using single species
Strong stemmed

 

Clematis Rope Hedges

 

All flower at the same time
All pruned the same method
All to have equal vigour

 

Winter Flowering Clematis

 

Some are less hardy
Most dislike cold wet soils
Often slow to establish
Some have good fragrance

 

Clematis For Shade

 

 Clematis Alba Luxurians
Clematis ‘Bees Jubilee’
Clematis viticella ‘Minuet’
Clematis ‘Wada’s Primrose’
Clematis macropetala ‘White Satin’
Clematis alpina ‘Willy’
Clematis montana ‘Wilsonii’

 

Clematis for North Walls

 

Shady and cool
Can be cold!
Damp or dry
Bright flowers
Ideal for pale clematis

 

Clematis for full sun

 

Clematis florida 'Sieboldiana’
Clematis ‘Rebecca’
Clematis texensis 'Gravetye Beauty'
Clematis texensis 'Princess Diana'
Clematis viticella 'Abundance'

 

Clematis with scent

 

Clematis armandii 'Snowdrift’
Clematis cirrhosa 'Calycina’
Clematis flammula (Hawthorn)
Clematis heracleifolia 'Cassandra'
Clematis rehderiana (Cowslip)
Clematis serratifolia 'Golden Harvest'
Clematis tangutica 'Lambton Park’ (Coconut)
Clematis terniflora (Sweet Autumn Clematis)
Clematis triternata ‘Rubrifolia’

Clematis as container plants

 

Must be dwarf
Must be able to withstand patio conditions
Can be used in combination with other plants
Keep pot and roots cool and frost free
Special winter care

 

Clematis Planting

 

Timing
Problems – base of wall, eaves, reflected heat, competition with other plants
Sufficient root development area
Shade for roots

 

Clematis Supports

 

Look natural
Natural materials – other plants
Free standing Ironwork
Away from walls on battens

 

Pruning Groups

 

RHS 27 ways
Newly planted all should be pruned except herbaceous types

Three methods Howard’s Way
One - Require no pruning
Two - Flower before 1st of August
Three - Flower after 1st of August

 

Group One (little or no pruning)

 

Only require pruning if outgrown their space
This category includes C alpina, C chrysocoma, C macropetala, C montana and the evergreen C cirrhosa and C armandii groups. If you wish to prune these types because they have outgrown their space they should be pruned immediately after flowering. You may or may not lose your plant as a result of over hard pruning. You might want to reduce the plant size over two or three seasons rather than in one go.

 

Examples of Group One Pruning

 

Clematis alpina AGM
C. alpina 'Pamela Jackman'
C. armandii
C. × cartmanii 'Avalanche'
C. × cartmanii 'White Abundance'
C. cirrhosa
C. cirrhosa var. balearica
C. cirrhosa 'Freckles’

C. cirrhosa 'Wisley Cream’ AGM

 

C. 'White Columbine' AGM
C. 'Constance' AGM
C. 'Frances Rivis' AGM
C. macropetala
C. macropetala 'Blue Bird'
C. 'Markham's Pink' AGM
C. montana
C. 'Rosy O'Grady'
C. 'Ruby'

Group Two (Little Pruning)

 

This category includes the early large-flowered forms including the double and semi-double cultivars. These plants produce their main flush of flowers in May and early June on stems made in the previous year so pruning is limited to cutting out dead or weak shoots in February.


After the early flowers have finished you can prune back some of the flowered shoots to encourage new growth. This is also the time to cut back a plant that has outgrown its position or which has become an unsightly tangle at the top. Again, be careful. Reduce the plant over two or three seasons rather than in one brutal prune.

 

Examples of Group Two Pruning

C. ‘Barbara Jackman'
C. 'Bees' Jubilee'
C. 'Belle of Woking'
C. 'Beauty of Worcester'
C. 'Burma Star'
C. 'Doctor Ruppel'
C. 'Duchess of ‘Edinburgh'
C. 'Edith'
C.  florida var. sieboldiana
C. 'Jackmanii Alba'

C. 'Jackmanii Rubra'
C. 'Marie Boisselot' AGM
C. 'Matka Teresa'
C. 'Nelly Moser' AGM
C. 'Snow Queen'
C. 'The President' AGM
C. 'Rebecca'
C. 'Royal Velvet'
C. 'William Kennett'

Group Three (Hard Prune)

 

This category includes the late large-flowered hybrids and the small-flowered viticellas, orientalis and texensis groups. These plants flower on the new season's growth. Prune in February by starting at the bottom of the plant and working your way up the stem to the first pair of plump, healthy buds. Prune the stem above the buds and remove everything above the cut. Treat each stem in a similar way. The plant will be encouraged to make strong new growth and an abundance of flowers.

 

Examples of Group Three Pruning

C. ‘Abundance' AGM
C. 'Alionushka' AGM
C. 'Étiole Violette' AGM
C. 'Ernest Markham’ AGM
C. 'Duchess of Albany'
C. 'Gravetye Beauty'
C. 'Lady Betty Balfour'
C. 'Polish Spirit' AGM

C. 'Princess Diana' AGM
C. 'Royal Velours' AGM
C. 'Ville de Lyon'
C. 'Sir Trevor Lawrence'
C. × triternata 'Rubromarginata' AGM
C. viticella
C. viticella 'Purpurea Plena Elegans'

Propagation Seed (Sexual)

 

Sown in autumn and exposed to elements

Cuttings (Asexual)
Twin leaved, late June leave outside

Layering
Slow, not often practised

 

Pests

 

Aphids
Caterpillars
Earwigs
Mice

Monkjack Deer
Rabbits
Red Spider Mite
Scale
Slugs and Snails
Vine weevil
Whitefly

 

Diseases

 

Fungal Leaf Spotting

Bacterial Black Death of Hellebores

Bacterial Slime flux

Powdery Mildew

Clematis Wilt

 

Clematis Wilt

 

95% of cases are not Clematis wilt disease
5% only caused by 3 fungal infections
Phoma clematidina is the most common
Main cause of wilting foliage is YOU
Knuckling caused by slipping on support
Ensure all foliage is properly tied to supports
Cut down
Spray with Fungicide during growing season
Tie in new growths as needed

 

Breeders, Nurseries and Suppliers

 

Ashwood Nurseries

Marcus Dancer Plants
Taylors Clematis Nursery
Thorncroft Clematis Nursery
Thompson and Morgan Clematis List
Walled Garden Nursery (Wilts)
Priors Wood Clematis

 

© Howard Drury 22/02/2020


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