Clematis delights in so many situations
They’re popular, they’re beautiful, and easy to grow. Stephen McCarthy sings the praises of the clematis.
Definitely among the world’s most beautiful climbing flowering plants, clematis are also one of the most popular with gardeners. They come in many sizes from diminutive examples like the one in the photograph, Clematis ‘‘Freckles’’, to giants which will grow 20 metres or more into a large tree. There are roughly 250 species of these plants and many more hybrids raised by nurserymen.
Old Man’s Beard Clematis vitalba is an exceptionally vigorous growing species in New Zealand where it has become a serious pest in many areas, seeding prolifically and growing very quickly to smother the trees up which it clambers.
Most clematis are definitely better behaved and make delightful garden plants, particularly useful for covering a trellis or growing up a small tree or draping shrubs to create a very informal romantic effect.
Clematis are quite easy to grow providing a most basic rule is adhered to : they do not like having their roots in hot sundried soil. Try to plant them in a position where the foliage can climb into a sunny spot and the roots are in shade.
Mulching the root area to keep it cool and moisture-retentive will greatly improve plant vigour. They will grow in a wide range of soils, preferring a good well-drained loamy soil to which wellrotted garden compost has been added plus some form of lime.
Probably the most popular and easy to grow is Clematis montana and its garden varieties. Being quite vigorous and with stems up to nine metres it is very useful for quickly covering an unsightly small shed, over walls or for use as an informal screen on a trellis. C. montana has garden forms coming in shades from white pale to dark rose pink.
Similar to our familiar native white clematis, the evergreen Chinese C. armandii is a vigorous climber with stems up to six metres long which produce a frothy, spectacular display of creamy-white flowers. Being frost tender it needs to be grown in areas where only light winter frosts are experienced.
The most spectacular flowers in the family belong to the large-flowered garden clematis section, being the product of complex hybridisation.
These produce often very large flowers up to 15 cm in diameter and in a wide range of colours ranging from white pinks, mauves, purple to burgundy red.
They look very spectacular when growing in combination with a climbing rose, making a deliciously sumptuous combination.
Like all clematis they are gross feeders and respond well to an annual mulch of well rotted manure or compost, plus ample water in the dry season.
Clematis can be kept under control by pruning back the longer shoots on the more vigorous varieties.
The large flowered section can be similarly pruned and can be completely rejuvenated by very hard pruning almost to ground level every so often. This treatment often produces a very good flowering the following season.
Clematis are usually grown from cuttings to keep the best flower forms as seedlings are variable. Also the size of the flowers varies with the sex of the plant in some species such as the well-known NZ native C. paniculata, which has larger flowers on female plants.
They are reasonably easy to grow from cuttings of hardened new growth taken about January. Cut the stems into sections just above every pair of leaves, with the stems being shortened to about 12cm if necessary. Insert the cuttings to a depth of about 5cm in a mix of sharp river sand plus a bit of sifted leaf mould around the edge of a large plastic pot.
Water the potting mix well and put the pot in a large sealed plastic bag in a light place but out of direct sunlight. Mist them regularly to keep the atmosphere and soil moist and they should develop roots within about six weeks, when they can be repotted in individual pots.
The thickish fleshy roots are fragile so be careful.
Beautiful climber: The charming small flowers of Clematis ‘Freckles’.