Clematis 'Asao'

Clematis 'Asao' was raised by Japanese breeder Kazushige Ozawa and ranks among the oldest and best-known large-flowered cultivars from Japan; it was introduced to the UK by Guernsey Clematis Nursery around 1980. Its 10–12 cm flowers glow vivid red to rose-pink, especially towards the petal margins, paling towards the centre where a striking golden-yellow eye of stamens creates a strong contrast. The early flowers often come semi-double, while the later flush is single.

'Asao' is one of the very earliest large-flowered clematis hybrids, blooming as early as May and June, with a further flush in July and August. At around 200 cm it stays pleasantly compact and is excellent for containers, small trellises and supports on fences or walls. It prefers a semi-shaded position — north-, east- or west-facing spots also suit it — since its vivid colour fades faster in hot, full-sun locations.

'Asao' is reliably winter-hardy (zone 6, down to about -23 °C) and easy to care for. Cut the plant back to about 75 cm after the first flowering in June to encourage vigorous regrowth and a rich second flush in summer. As one of the oldest varieties in its group, 'Asao' has proven itself in gardens for decades and is considered robust and reliable.