Anthriscus sylvestris

Anthriscus sylvestris Ravenswing in bloom, Chelsea Flower Show, London, 2013

Hailing from Europe, Caucasus, Turkey, north-west Africa, the original species of this plant is colloquially called 'cow parsley' and is a vigorous inhabitant of European hedgerows and meadows. It is a relative of the herb chervil (Anthriscus cerefolium), which has the same ferny foliage. The cultivar 'Ravenswing' has gorgeous purple-brown lacy leaves and umbels of tiny white flowers on 1 m stems from late spring to summer. It does better in cooler climates, where it is more likely to bloom, but as a foliage plant I think it is OK in Sydney, though it will never flourish the way it does in English gardens. It prefers well-drained soil in sun or part shade. It self-seeds readily in cool-climate gardens. Strictly speaking, it is a frost-hardy biennial or short-lived perennial; mine, which has never flowered, has been around for a number of years!