Herbaceous Clematis, Clematis Viticella and Clemetis Texensus Cultivars
Clematis Viticella and Its Hybrids
All the cultivars in this section stem from crosses with the European species Clematis viticella, which in late summer produces a massive profusion of pretty little mauve bells. This species has been in cultivation in this country since the 16th century, and is still very popular today.
Because of the parent species, all the cultivars flower very profusely, and all of them are in bloom through August and September. The colour range has become very diverse, ranging from the red of Clematis viticella Abundance’ to the purple of C ‘Etoile Violette’, with whites and pinks in between. There is also the only double variety to flower so late in the year – the unfortunately named C. v. ‘Purpurea Plena Elegans’.
All these hybrids benefit from a hardeach year. Thanks to their general vigour and tenacity for life, they are ideal for growing through and up other trees and shrubs that flower earlier on, or combined with shrubs with ornamental foliage, where the combinations of colours can be extremely attractive.
It seems slightly odd that the first recorded clematis hybrid was a herbaceous one. It was named Clematis X eriostemon, and was the result of a cross between the two European species C. integrifolia and C. viticella. With its bright-blue bells this herbaceous clematis is still very much worth growing. Among the most eye-catching combinations that can be seen is a C. X eriostemon tumbling over a wall covered with a golden-foliaged ivy such as Hedera helix ‘Gold Heart’.
The term ‘herbaceous’ is used to denote those plants which die down to a basal clump each year, and this is exactly what these herbaceous clematis do. They can be treated like any other herbaceous plants, and can be lifted and divided in the autumn as required. They also need support – and while semi-herbaceous forms such as Clematis x durandii or C. integrifolia will happily clamber through other plants, others such as C. heracleifolia or C. recta will need the assistance of pea sticks, or one of the many herbaceous plant supports now available.
These last two species and their varieties make big plants indeed. As they only bloom once, and for a short period at that, they are perhaps best avoided in a small garden. However, they do possess a good scent, which attracts a variety of insect life. Butterflies in particular love to feed on the nectar of Clematis recta, adding extra colour to a plant that is otherwise rather dull.
The purple-leaved form is rather better, and is worth seeking out.
In common with all clematis, these herbaceousrespond well to generous feeding and copious amounts of water. They can provide a useful addition to your mid-summer garden.
Clemetis Texensis Cultivars
Clematis texensis is an intriguing plant. The flower is bright red I the best forms, and its shape is that of a small tube. This species appears to be a rather spindly grower, yet in the latter pat of the 19th century it formed the basis for a number of hybrids named after various members of the nobility. They were produced by a Woking-based nursery, so became known as the Woking-ensis hybrids. Alas, very few of them have survived to this day – but those hybrids that have survived, together with some of the modern cultivars, are some of the most stunning plants that you are likely to find anywhere.
Oddly enough, many of the modern forms continue the noble tradition. Clematis texensis ‘Princess of Wales’ and Clematis texensis ‘Ladybird Johnson’ are amongst the finest. Produced by Barry Fretwell at his Peverill Nurseries, the ‘Princess of Wales’ is a wonderful deep pink that almost glows, while ‘Ladybird Johnson’ is a deep wine-red. Both these new forms deserve a place in even the smallest garden.
All the texensis cultivars are perfectly hardy. By their very nature, however, they tend not to climb, preferring to scramble through other shrubby plants, where their upturned tulip-shapedare produced in abundance, adding a quite exotic touch to the late-summer borders.
The clemetis texensis are all moderately vigorous in growth, so are best planted together with a comparable host – perhaps one of the low-growing cotoneasters, or the silver-leaved berberis with the dreadful name ofdictyophylla approximata. Both of these will provide the support the clematis requires without themselves becoming swamped and spoiled.
Experience suggests that these varieties dislike being planted in tubs or containers, which are prone to dry out. Under such conditions, and also in dry positions in the garden, these plants will soon develop, which if left unchecked can soon defoliate and eventually kill the plant.
Other Clematis Species and their Hybrids
The genus Clematis is represented in every continent. This means these plants can be grown in a variety of climates andtypes, ranging from the chalky to the very acid.
In general, clematis arethat use their leaf stems to attach themselves to their host plants. However, there are also herbaceous clematis forms that die down to ground level each year – Clematis heracleifolia from China, for example. Then there are those such as the European species C. viticella that will happily scramble along the ground while still providing a good display of flowers.
The fact that clematis are so diverse means that the range of flower shapes and colours available is also very extensive. China alone has given us the delicate yellow bells of Clematis tangutica, together with those large, exotic-looking blooms produced by crossing C. florida with C. patens and C. lanuginosa.
Australasia, with its unusual natural history, provides some fascinating curiosities. Clematis marmoria is a tiny, white-flowered species that is best treated as an alpine, while C. afoliata is remarkably unusual, having replaced its leaves with tendrils and looking very like a climbing rush.
Africa is represented by Clematis brachiata – a vigorous, almost evergreen climber with white-flushed green flowers and a slight scent.
The most scented species of all, however, is Clematis flammula, which comes from Europe. Its growth is very vigorous, and the small white star-like flowers give off the most wonderful vanilla scent in midsummer.
Also from Europe is the semi-herbaceous Clematis integrifolia. This is best grown over a low wall, where its bright-blue bell-shaped flowers, recurved at the tips, can be seen to best effect.
The only species native to Britain, Clematis vitalba, is probably better known for its display of seed heads than for its flowers, which are usually disappointingly small and off-white in colour. It is the seed heads that have earned it the common name of old man’s beard. They make a wonderful autumn display along country roadsides, where after a heavy dew the fluffy tassels glisten in the early morning sun.
America is the home of the popular Clematis texensis, much prized for its brilliant scarlet, tubular flowers. It is unfortunately a rather weak grower, and the hybrids are probably a better choice for the garden.