Propagating Vallisneria 'Contortionist' (Corkscrew Val)

How to propagate the twisted corkscrew Vallisneria asiatica var. biwaensis through runners and daughter rosettes, with rooting, lighting and substrate tips.

Overview

Vallisneria 'Contortionist' is a decorative form of the corkscrew tape grass with tightly spiralling leaves. Like all Vallisneria it grows as a rosette: the leaves arise in clusters directly from the roots rather than from a stem. Because it is a rosette plant, you never top or cut the main stem to multiply it.

Vallisneria spreads by runners and forms tall underwater meadows. Daughter plants develop at the ends of the runners, and once a plant settles in it multiplies readily, making this one of the easiest aquarium plants to propagate.

Propagation Method

The natural and only practical method is runner (stolon) division. The mother rosette pushes horizontal runners through the substrate, and each runner produces a new daughter rosette that roots into the gravel on its own.

Step-by-Step

Let the parent plant establish until you see horizontal runners spreading through the gravel.
Wait for a daughter rosette at the end of a runner to grow several of its own leaves and a small root tuft.
Cut the runner connecting the daughter to the mother once the daughter is rooted and self-sufficient.
Lift the daughter rosette gently and replant it in fresh substrate, spacing it so it has room to spread.
Bury only the roots, keeping the crown (where leaves meet roots) at or just above the substrate surface.

Conditions for Healthy Growth

Vallisneria tolerates bright illumination but does well under moderate lighting, so a quality planted-aquarium LED is recommended. It does not require CO2 fertilisation. It prefers neutral to alkaline water and dislikes very acidic conditions; it even tolerates slightly brackish water.

Maintenance

Once settled, the plant spreads continuously through the gravel. Thin out and remove daughter rosettes wherever it grows somewhere you don't want it; they pull up easily. Periodic dosing of fertiliser and good light keep the spiral leaves firm and full.

Common Challenges

The most common mistakes are burying the crown (which causes rot) and very acidic water, which Vallisneria does not like. If runners stop forming, check lighting levels and add iron-rich root fertiliser, since this is primarily a root feeder.