Rotala mexicana is a stem plant relatively new to the hobby.
As it is found in many tropical and subtropical regions of the earth, e.g. in South America, Western Africa, Australia and Japan, it is not really surprising that this species is very variable. In botanic literature, plants with large areas of distribution often have several synonyms - as does Rotala mexicana. One of them is Rotala pulsilla, under which name this plant is also known in the hobby.
The first R. mexicana variety that went into trade originated from South America and was offered by the Japanese company Rayon Vert. It was first listed as Rotala sp. 'Araguaia'. Varieties from Australia and other regions are still rare and difficult to obtain.
The South-American variety R. mexicana 'Araguaia' is a plant that either thrives or dies off. It needs strong unhindered light and an ample supply of CO2, macro- and micronutrients. The plant reacts to a lack of any of these factors with blackening, or crippled and stunted growth. Low nitrate levels cause the stems to attain an intensive red. However, limiting nitrate cannot be recommended as the danger of stunted growth is a very real one, even if an elevated iron level might compensate for it.
When kept in good conditions, this plant grows fast and lush, almost weedlike. As it branches readily, too, propagation by cuttings is not a problem.
As its relative R. rotundifolia, R. mexicana is a wonderful background plant. You can also create a hedgelike planting with it in the middleground, given that you are willing to trim it frequently.
Its reddish stems and pointy yellowish green leaves make R. mexicana a beautiful and very recommendable plant for every hobbyist who can fulfill its needs.
<a href="http://www.flowgrow.de/db/aquaticplants/rotala-mexicana-araguaia" target="_blank"><img alt="Rotala mexicana "Araguaia"" title="Rotala mexicana "Araguaia"" src="http://www.flowgrow.de/db/widget/aquaticplants/rotala-mexicana-araguaia" /></a>
[widget=aquaticplants/rotala-mexicana-araguaia]Rotala mexicana "Araguaia"[/widget]