Botanical name: Romulea rosea
Common Names
Onion Grass, Onion Weed, Onion-Grass, Rosy Sandcrocus
Romulea rosea is a herbaceous perennial plant in the family Iridaceae. It is a small plant, usually less than 20 cm high, with grass-like leaves. The flowers, which appear in spring, are pink with a yellow throat. Common names include Guildford grass, onion grass and rosy sandcrocus.
R. rosea is endemic to the western Cape Province (now Western Cape, Eastern Cape and Northern Cape) in South Africa, but it has become naturalised in Europe, Australia, New Zealand, and California in the United States. It is considered to be an environmental weed in much of Australia.
Plants 3–12(–30) cm. Corm tunicate, 5–15 mm diam.; tunic hard, woody, splitting above and below into acuminate segments, those below bent backward. Stems usually branched below ground level; branches (peduncles) aerial, suberect, becoming falcate, ultimately erect. Leaves (2–)6–9, much exceeding stem; blade 10–30 cm × ca. 1.5 mm. Spathes green or flushed with purple; outer 12–25 mm, margin narrow, membranous; inner margin brown-streaked, broad, membranous. Tepals pink to purple, usually pale yellow in cup, outer pale abaxially, main veins dark green to purple, lanceolate, 13–22 × 3–4 mm; perianth tube 2–3.5 mm; filaments ca. 5 mm; anthers ca. 4 mm; style branching opposite upper 1/3 anthers; branches ca. 2 mm, shorter than anther apices. Capsules 10–15 mm. Seeds ca. 2 mm diam.
SIMILAR SPECIES
Looks like a grass and behves like an annual, dying back at the end of summer.
SCENARIOS AND SOLUTIONS:
- In lawns: get a cotton rope and soak it in Apparent Glyassist and Apparent Glyphosate and suspend above the lawn without touching the ground, high enough to only make contact with the Guildford Grass.
- In garden beds: Apparent Bowsaw Metsulfuron.
References:
https://bie.ala.org.au/species/https://id.biodiversity.org.au/node/apni/2896357#overview
https://grasslands.ecolinc.vic.edu.au/fieldguide/flora/onion-grass#details
