Propagating Rotala mexicana 'Bangladesh' from Cuttings

How to propagate the fine-leaved Rotala mexicana 'Bangladesh' by stem cuttings: an easy, fast grower that shows green to orange-red colour under bright light and CO2.

Overview

Rotala mexicana 'Bangladesh' is a fine-leaved form of Rotala mexicana, a stem plant of the loosestrife family (Lythraceae); the 'Bangladesh' trade form is generally treated as a form of R. mexicana, though there is some taxonomic uncertainty. It is a thin-leaved, fast grower that stays mostly green with a dark burgundy stem and develops red to orange hues only under very intense light. It is propagated vegetatively from cuttings.

Propagation Method (Cuttings)

'Bangladesh' is propagated through stem cuttings, like other Rotala. Cut the longest stems 5-10 cm from the substrate and replant the tops in groups. One quirk of this form: it is not a prolific brancher, and when topped the remaining top portion tends to rot back while a few side shoots form lower down the stem — so favour replanting healthy cut tops over relying on the trimmed base.

Step-by-Step

1. Choose a healthy stem with good fine foliage, at least 10-12 cm tall.
2. Cut the top 5-10 cm with clean, sharp scissors.
3. Strip leaves from the lowest 2-3 cm to expose a clean node.
4. Plant the cutting into nutrient-rich substrate, burying the stripped node; group several for a streamlined mid-stem stand.
5. Watch the topped base: expect a few low side shoots rather than dense branching, and remove any rotting top stub.

Conditions for Healthy Growth

This form is forgiving but rewards good conditions. It grows in lower light, but 80+ umol PAR promotes better colour, and 150-200 umol PAR gives the strongest colouration — red only under the most intense light, otherwise green with a burgundy stem. CO2 is not required, yet with sufficient light and CO2 the plant grows denser and more colourful. Soft, slightly acidic water suits the mexicana group well.

Trimming & Maintenance

Once established 'Bangladesh' behaves like a weed and can trail long stems along the surface in high light, so trim regularly — roughly every week or two — to keep the group tidy and light reaching the base. Because topping causes the cut top to rot rather than branch heavily, the cleanest long-term method is to harvest and replant fresh tops each cycle. Like other Rotala it is amphibious, so emersed-grown stems convert their leaf form as they settle in submersed culture.