Propagating Rotala macrandra 'Mini' from Cuttings

How to propagate the compact red cultivar Rotala macrandra 'Mini' by stem cuttings, and how to keep its deep colour with strong light, CO2 and soft water.

Overview

Rotala macrandra 'Mini' is a compact selection of the demanding red stem plant Rotala macrandra, a species native to Asia. Like the parent species, it develops beautiful red shades only under very good light, and it is rated an advanced plant because it is sensitive to unstable conditions.

Being a cultivar, 'Mini' is propagated in exactly the same way as the wild species: vegetatively, from stem cuttings. It does not need seeds or special equipment, only healthy stems and stable water.

Propagation Method (Cuttings)

The standard method for Rotala macrandra and its cultivars is topping: you cut the upper part of a healthy stem and replant it, while the remaining base produces new side shoots. This multiplies the plant and thickens the group at the same time.

Step-by-Step

1. Choose vigorous, well-coloured stems with no signs of melting at the base.
2. Cut the longest stems about 5-10 cm from the substrate, following the same approach Tropica gives for the parent species.
3. Strip the lowest leaves from each cutting so a clean section of stem can be buried.
4. Replant the cuttings back into the same group, spacing them so light reaches each stem.
5. Leave the trimmed bases in place; they will branch and send up new side shoots.

Conditions for Healthy Growth

Strong colour and successful rooting of cuttings both depend on the same factors: high light, added CO2 and a full set of nutrients including iron. The parent species is described as requiring soft water, so 'Mini' is happiest in soft, stable water rather than hard or fluctuating tap water.

Trimming & Maintenance

Regular topping keeps the group dense and constantly supplies new cuttings. Each trim removes the shaded older growth and encourages bushy, well-lit shoots. Emersed culture is possible for this species, but submersed growth under high light and CO2 is what produces the prized red form, so most aquarists keep and propagate it fully submersed.

Common Challenges

Pale or green leaves usually mean light, CO2 or iron are too low for a red plant of this demand. Lower-leaf loss and thin stems point to shading or unstable conditions. Keep parameters steady, prune before stems flop, and only the strongest tops will reward you with deep colour.