Vallisneria spiralis "Tortifolia"

Vallisneria spiralis “Tortifolia” is a growth form of the eelgrass with spirally twisted, ribbon-like leaves; in the trade it is also known as “Contortionist”, “Torta” or Vallisneria torta.¹ An older record gives California and Nevada as its origin, and its import from California is dated to 1906/07.¹ The species V. spiralis itself, by contrast, is native from Europe to Indochina and in southern Africa, but not in North America.¹²

While the species is regarded as undemanding, the decorative twisted form is somewhat more demanding in cultivation.¹ For the species, fine-grained sand as substrate and medium-hard to hard, alkaline water rich in carbonates are recommended; it is propagated by runners.¹ It is easily confused with Helanthium bolivianum 'Vesuvius', whose submersed leaves are likewise twisted like a corkscrew.³