Cyperus involucratus (CYPERACEAE) Umbrella Sedge

Weeds to Whack

Infests damp areas

An escaped garden plant native to Africa still favoured in gardens throughout the catchment as an attractive ornamental. It has become a fast-growing weed infesting damp areas, particularly creeks. It has leaves which are reduced to sheaths and stems to 120 cm. The seed heads have bracts (leaf-like growths) in a whorl, spreading like an umbrella, hence the common name. These large leafy bracts are often mistakenly assumed to be leaves. Hairless, rigid, slightly ridged stems to 5 mm thick are three-angled or almost cylindrical in cross-section. The seed head (inflorescence) has numerous stalks (5-10 cm long) radiating from the top of the stem. Flower spikelets are initially light green in colour, but turn reddish-brown as they mature. Yellowish, oval-shaped seeds are triangular in cross-section. Quite a lot growing along Enoggera Creek following flooding.

Cyperus involucratus Umbrella Sedge growing underneath Walton Bridge on Enoggera Creek in June 2026. Photo: Anne Jones

Inflorescence. Photo: Robert Whyte

Cyperus involucratus Umbrella Sedge growing with Ruellia tweediana also a weed. Photo: Robert Whyte

Photo: Matt Tomkins