Propagating Rotala sp. 'Vietnam' from Cuttings

A practical guide to propagating the pink-orange rotundifolia-group cultivar Rotala sp. 'Vietnam' by stem cuttings, with notes on light, CO2 and colour.

Overview

Rotala sp. 'Vietnam' is a slender cultivar in the Rotala rotundifolia group, valued for the pink-orange tones its narrow leaves develop under good light. R. rotundifolia is a hardy, widespread Asian plant whose submerged leaves are narrow and lanceolate, and 'Vietnam' shares that fine, whorled texture.

As a selected form of rotundifolia, it is increased the same way as the parent: vegetatively, from cuttings. Wikipedia notes plainly that R. rotundifolia "is propagated by cuttings", and the cultivar behaves identically.

Propagation Method (Cuttings)

Propagation is by topping. You cut the top of a healthy stem and replant it as a new plant; the base that remains branches into several side shoots. Repeating this turns a few stems into a full, textured group.

Step-by-Step

Select healthy, upright stems; the strongest tops carry the best pink-orange colour.
Cut the upper 5-10 cm of each stem with sharp scissors.
Remove the lowest whorls of leaves so a bare node can be planted.
Push each cutting into the substrate and group several together for a fuller look.
Keep the trimmed bases; they will send out new side shoots from the remaining nodes.

Conditions for Healthy Growth

R. rotundifolia is described as undemanding but requiring light to thrive, and under strong light its leaves can turn almost wine red. For the warm pink-orange of 'Vietnam', give the cuttings strong light, added CO2 and iron-rich fertilisation with lean nitrate; losing lower leaves is a classic sign of too little light.

Trimming & Maintenance

Trim on a regular cadence to keep the stand bushy and to harvest cuttings. The species can also be grown emersed in shallow water, where the leaves become rounder and it may flower, but the slender submersed form is what aquascapers propagate. Frequent topping under high light keeps the colour and texture at their best.

Common Challenges

If 'Vietnam' refuses to colour, light or CO2 is usually the limit, not fertiliser alone. Thin, stretched stems with bare lower sections mean shading. Keep the group trimmed and well lit, and replace any melted cuttings with fresh healthy tops.