If you are asking if "red stems" is a genetic trait, the answer is yes.
You did not say if your Nasturtiums are a single cultivar or mixed colors.
If they are mixed, you should expect some variability in other characters
besides flower color.
Night23 <night23 at nightynight.com> wrote in message
news:3B18096D.ABEC30FA at nightynight.com...
> I am growing a jar of Nusturtium plants from seeds. Among the 10 or
> so plants in the jar which have recently germinated, I observed that one
> of them has a red stem (the rest are green). The entire stem is a light
> red color including branches leading up to the leaves. The leaf
> venation is slightly reddish as well as well as a thin region of red
> around the rim of each leaf.
>> Is this a mutant plant?
>> Are there any physical (nutrient deficiency) factors that could cause a
> plant to have a red stem? The plants are closely spaced growing in the
> same jar and recieve the same amount of lighting everyday and the same
> amount of water (I haven't been adding red dye in or anything). Soil
> conditions are the same obviously since they are in the same jar.