Tufted stoloniferous aquatic perennial herb, the stolons rooting at the nodes. Leaves basal, strap-like, to 3 m long and 4 cm wide but mostly smaller. Stamens 2. Fruits drawn to the substrate by the spiralling stem. Grows in still or flowing water to 7 m deep. In gardens it is used in ponds but also used in cold and warm-water aquaria.
[V. spiralis of authors not L.]
This species is in need of revision. It encompasses a range of variation including the cultivar 'Torta' ['Contorta'] with tightly spiralled leaves and plants that are possibly hybrids. Sometimes available in horticulture asV. spiralis and possibly V. denseserrulata.
Source: (2005). Hydrocharitaceae. In: . Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.