This stoloniferous aquatic perennial forms tufts of long bright green ribbon-like leaves that are submerged in fresh water. It form large clumps and small white female flower are produce on spiral stems during late summer. 

Hardiness zones 9 to 12 

Vallisneria gigantea is naturally found from Australia to southern and eastern Asia, Europe and Africa. It grows in cold or warm fresh water along creek margins and in ponds. 

It prefers an open sunny position growing in a variety of wet soils and is frost and drought tender.

Ribbon Weed is grown for its foliage and is planted in domestic ponds or aquariums as a specimen. It is also used in large ponds for aeration and fish protection. It is suitable for coastal and inland regions. It establishes in one season and may be a weed in some areas. ID 1937

Note:
Under optimum conditions it may become a weed causing problems for irrigation systems. 

Vallisneria (val-lis-NER-ee-ah) gigantea (jy-gan-tee-ah)  

Hydrocharitaceae (HY-dro-KAR-ee-TAY-see-ee)