2 replies to this topic

[Robert Lamb]

Could I keep it in my pond year round in SE TN?

[swampfish]

It probably depends on which Vallisneria you have and where it came from. According to Kasselmann's 2003 Aquarium Plants book, Vallisneria americana is native to North and Central America, eastern and southeast Asia, and Oceania including Japan. It is native to central Illinois, where I live. I have successfully kept that which I bought at a local nursery in my pond over the winter. Conversely, I currently have some I collected in local ponds and have kept it for several years in my unheated aquariums in my basement where the temperature ranges from 54 to 76 degrees F from winter to summer. If you buy V. americana in a local fish store as "Jungle Val," it may be from a more tropical region and may not be hardy in your climate. 

 

So-called Italian Val is probably Vallisneria spiralis var. spiralis, according to Kasselmann, which is native to Europe and southwestern Asia. There is some thought that it is a separate species. Vallisneria spiralis var. denseserrulata is native to Africa, Asia, Oceania, and Australia. These may or may not be hardy in your ponds depending on geographic source. 

 

Corkscrew val is a variant of American Vallisneria. I have seen it in SE US streams. The scientific name Vallisneria spiralis refers to the flower stalk, not the leaves.

 

Phil Nixon

[gzeiger]

I have it growing wild locally in NJ, where flowing streams often freeze an inch deep.

 

Even in SC, the habitats where it is most common are shallow streams where winter water temperature is regularly in the mid to upper 40s F.