Singapore Daisy

Singapore daisy is a low, mat-forming perennial groundcover that spreads by trailing stems rooting at the nodes as they touch soil. It forms a dense carpet 15-30cm high but can scramble higher over shrubs, fences and other plants when given support. The stems are somewhat fleshy and root readily wherever they contact moist soil, which is the main reason it spreads so aggressively.

The leaves are dark green, glossy, and arranged opposite each other along the stem. They're roughly oval to lance-shaped with a distinctive three-lobed tip (the species name 'trilobata' refers to this), toothed margins, and grow to about 5-10cm long. The flowers are bright yellow daisies, around 2-3cm across, produced on short stalks above the foliage and appearing more or less year-round in warm climates, peaking in the warmer months.

This is a garden escapee originally from Central and South America, introduced as an ornamental groundcover for its ability to quickly cover bare ground. It's now a declared weed in Queensland and New South Wales and is a serious environmental weed along the eastern seaboard, invading disturbed bushland, waterway margins, roadsides and coastal areas from northern NSW through Queensland and into the Northern Territory. It tolerates full sun to part shade and a range of soils, but does best with reliable moisture and warmth, so spread is most vigorous in subtropical and tropical regions.

Management relies on preventing any stem fragments from being left in contact with soil, since even small pieces can re-root. Physical removal needs to include all runners and root fragments, followed by disposal well away from soil contact (not just left on top of garden beds). Because of its ability to smother native vegetation, many local councils and catchment groups run coordinated control programs, and it's worth checking with your local council on any legal obligations to control it on your property.