Onion Grass (Romulea rosea) – Weeds of Melbourne

Onion Grass (Romulea rosea), the ubiquitous magenta stars that adorn Melbourne’s springtime lawns.

Onion Grass is a plant that requires many more than 2200 characters, today we’ll recall its Australian history only to 1907. Imported from the Cape Colony as an ornamental bulb (and perhaps a hay and seed contaminant), by 1842 it had been collected on Sydney’s Dawes Point. At Melbourne the species was said to have been abundant around the Botanic Gardens by the c. 1870s.

Real infamy began when it established up the Swan River from Perth, quickly earning the moniker ‘Guildford Grass’ in that peculiarly WA custom of referencing a plant to ‘the name of the place where it became particularly obnoxious.’

A ‘bulbous weed at Guildford’ was noted in support of a motion passed at WA’s 1895 Fruit Growers conference which requested replacement of that colony’s overly narrow ‘Spanish Radish and Scotch Thistle Act’. The ‘Guildford Weed’ was mentioned again in the Assembly the next year as a new Noxious Weeds Bill moved to second reading. In 1897, ‘Guildford Grass’ made its first appearance in newsprint.

Spread by corm and seed along road verges and thence into poorly managed pastures, the plant would not be contained to Perth suburbs. At Bunbury, the Land Inspector wrote in 1900 that the Guildford Grass was ‘rapidly coming south and is…as great a curse as any.’ By 1905 it had been found ‘for some years’ at Bridgetown, 270 km S of Perth, where locals sought destruction of plants called a ‘curse’ and an ‘evil’ and one journalist suggested ‘two experiments, one with kerosene and the other with a solution of arsenic…We have never heard of a case where it has failed to kill plant life.’

Back in Victoria, the plant was also spreading rapidly, with ‘wide areas in Dandenong, Clayton and Moorabbin…covered with this pest,’ and ‘hundreds of acres of first-class grazing land’ ‘destroyed’ at Gisborne. In 1907, the year it was proclaimed a thistle in this state, field naturalist T.S. Hall recorded flocks of Sulphur Cockatoos digging up and eating the corms.