Propagating Myriophyllum sp. 'Guyana' from Cuttings

A practical guide to multiplying feathery Myriophyllum sp. 'Guyana' by topping the stems and replanting cuttings, with the light and CO2 it needs to stay dense.

Overview

Myriophyllum is a submersed aquatic plant with elongate stems carrying internal air canals and finely, pinnately divided whorled leaves. The 'Guyana' form is a fast-growing background milfoil whose airy, needle-like foliage stays bright green and compact only under intense light and added CO2. Propagation is simple because the genus is a fragmenting plant whose detached stem pieces readily grow back.

Propagation Method (Cuttings)

Like all milfoils, 'Guyana' is multiplied by topping: you cut the upper portion of a healthy stem and replant it as a new individual. The cut base left in the substrate then pushes out side shoots, so a single topping turns one stem into several over time.

Step-by-Step

Choose a vigorous, brightly coloured stem with dense whorls.
Cut the top 5–10 cm cleanly with sharp scissors.
Strip the whorled leaves from the lowest 2–3 cm of the cutting.
Plant the bare base into the substrate so it stays anchored.
Leave the original base in place to sprout new side shoots.

Conditions for Healthy Growth

Cuttings root and bush out fastest under high light with injected CO2; without both, the fine whorls thin out and the stem stretches. Keep water in the soft, slightly acidic range and provide rich water-column nutrients, since this is a hungry, fast grower.

Light: high intensity to keep whorls tight.
CO2: required for dense, lush feathery growth.
Temperature: roughly 22–28 °C, soft to moderately hard water.
Nutrients: high demand — dose the water column regularly.

Trimming & Maintenance

Trim roughly every ten days while growth is strong. Each topping both controls height and supplies fresh cuttings, so regular trimming and propagation are the same task. Replant the best tops and discard leggy lower sections to keep the stand even and full.

Common Challenges

Thinning or bare lower stems when light or CO2 is too low.
Stretched, sparse whorls in shade — raise light before re-trimming.
Loose fragments drifting off and re-rooting elsewhere, since the genus regrows from fragments.
Damaged feathery tips from rough handling during planting.