A well-drained, limy soil presents many problems to the gardener, but, by way of compensation, he will have spectacular results with clematis. The large-flowered hybrids are hardy climbers which bloom over an exceptionally long period, some for four or five months, and the choice is wide. One of the most exciting is ‘Perle d’Azur’, of a colour which is rare in the clematis family, sky-blue with scarcely a tinge of mauve, and a succession offrom mid-summer for at least eight weeks. ‘Mrs Cholmondeley’ blooms for even longer, from early summer into autumn, with enormous lavender-blue flowers, but austere critics complain that the sepals are too narrow for perfection. Both these hybrids will grow to 10 feet (3 m), best, in my view, on trellis, though some gardeners grow them through shrubs, an informal method better suited to the small-flowered species. There are also varieties in all shades of mauve, purple, red, and white, as well as some with striped flowers, like the celebrated mauveand- ‘Nellie Moser’.
These clematis like to flower in the sun. but to have theirin the shade, so shelter the roots with a ground-cover plant, or with tiles or stones. will flower over a longer period, and be richer in colour, on an east, west, or even a north wall, rather than on a south wall.
Plant in a large hole with plenty of rotted manure orbelow the roots, work some peat among the roots, and add grit to the soil if it is not naturally well-drained. After planting, cut back the shoots in the first spring to 12 inches (30 cm) from the ground, and the summer-flowering hybrids every following spring to 5 feet (150 cm), each above a pair of strong buds. 9