Although clematis is more associated with summer, there are some very beautiful kinds for spring flowering and they are generally easy to grow. These are in flower now, a little earlier than usual due to the mild spring weather.
The alpine clematis, Clematis alpina, is a deciduous species native to continental Europe, and is a moderate grower reaching three metres. Though delicate in appearance with light twiggy stems and neat foliage, it is able to withstand cold weather.
It has elegant, nodding, bell-shaped flowers with four pointed petal-like sepals in rich inky blue and a white centre. The wild species shows some variability and a range of colour selections have been named, such as 'Constance' with semi-double purplish pink flowers; 'Pink Flamingo' with pale pink flowers, also semi-double, and 'Frances Rivis' with blue flowers.
From China, Clematis macropetala is the oriental equivalent of the European alpine species, also deciduous. Surviving even in parts of Siberia, it can be grown in a cold locality and tolerates wind exposure. About two to three metres tall, it climbs well on a fence or reasonably open shrub, which suits it because it can appear a bit straggly growing on its own.
The flowers also have that appealing nodding habit with somewhat bigger flowers in soft blue or pink. The flowers have slender petals inside the outer petals, a structure that gives them a semi-double appearance. The plain blue species is very pretty and 'Markham's Pink' has dark pink flowers against light green leaves.
The mountain clematis, Clematis montana, is also from China, but it is much more vigorous, deciduous, capable of growing 15 metres or more across. It makes a big mound of stems and smothers itself with smallish, but very pretty, flat white flowers.
Most of the kinds grown in gardens are pink forms, such as the lovely 'Elizabeth' with dark-tinged leaves and pale pink scented flowers. 'Tetrarose' has dark pink flowers. While the smaller mountain species can be grown through a loose shrub, such as pyracantha, this species is much too vigorous and shades out any tree or shrub on which it is grown.
Another Chinese species, this one evergreen, Clematis armandii, is very beautiful for its large trusses of small white flowers. This needs to grow on a fence or wire supports on a wall. All kinds grow in well-drained soil.