Propagating Rotala 'Sunset': Cuttings for Warm Color

How to propagate Rotala 'Sunset', an orange-yellow cultivar of Rotala rotundifolia, using stem cuttings and topping while strong light, CO2 and iron drive its warm color.

Overview

Rotala 'Sunset' (a 'Colorata'-type cultivar of Rotala rotundifolia) is prized for warm orange-to-yellow tops. Its parent, Rotala rotundifolia, is in the family Lythraceae, is native to Southeast Asia where it grows as a common weed in rice paddies and wet places, and under strong light its leaves can turn almost wine red. 'Sunset' carries that responsiveness toward orange hues and is propagated exactly like the parent: by cuttings.

Propagation Method

Rotala rotundifolia is propagated by cuttings and forms side shoots willingly, so 'Sunset' multiplies the same way. Cutting the colorful top and replanting it produces a new stem, while the trimmed base branches into several new shoots. This makes a single planting expand quickly into a dense, bushy group.

Step-by-Step

Cut the top 5-10 cm of a brightly colored stem with clean scissors.
Strip leaves from the lowest 2-3 cm to free a node.
Replant each cutting separately in nutrient-rich substrate.
Leave the trimmed base in place; it will throw out side shoots.
Maintain strong light and CO2 so new tops develop their sunset color.

Conditions for Healthy Growth

This is an intermediate, medium-growth cultivar. The parent is relatively undemanding but needs good light to produce its red and warm colors; for the 'Sunset' orange tones, strong light, CO2 and adequate iron are what bring out the hue. Provide warm water (about 20-28 °C), soft to moderately hard water, and a nutrient-rich substrate. Note that this cultivar is grown submersed; the submersed leaves are narrow and lanceolate, unlike the rounded emersed leaves of the wild marsh form.

Trimming & Maintenance

Because the plant becomes compact and bushy it blocks light from its lower foliage, so frequent pruning is needed; trim roughly every ten days. Each trim both keeps the group dense and supplies fresh, well-colored cuttings to replant and thicken the stand.