Green foxtail

Overview

Green foxtail (Myriophyllum mattogrossense) is a delicate, feathery stem plant with whorls of finely divided, bright-green leaves that create a soft, airy texture in the background of a tank. It is a fast grower that fills space quickly and, like other fine-leaved stems, is superb at outcompeting algae by consuming nutrients rapidly. The trade-off for those intricate leaves is a slightly higher demand for light and nutrients than plain-leaved plants: give it enough and it is gorgeously lush; starve it of light and it turns thin and straggly.

Planting & placement

Green foxtail is a stem plant for the background. Plant the stems individually into the substrate a couple of centimetres apart with tweezers, and always in a group — a dense stand of many stems is what creates the beautiful feathery “bush,” while isolated stems look sparse. It grows tall (30–50 cm) and can reach the surface. See how to plant aquarium plants for the technique and aquascaping for beginners for arranging soft-textured backgrounds.

Light, CO2 & ferts

Fine-leaved plants are hungrier. Give green foxtail medium-to-high light — see our best light for a planted tank guide — to keep the whorls tight and dense; too little and it goes leggy. Injected CO2 is recommended for the fullest, most compact growth, though it can manage without in bright tanks. As a fast, feathery feeder it wants a regular complete fertilizer dose from our best plant fertilizer picks.

Propagation & problems

Propagation is the classic stem-plant method: trim and replant. Snip a healthy top, push the cutting into the substrate, and it roots quickly; the cut parent branches below for a denser group. You will trim often thanks to its speed. The main problems are legginess from weak light and a straggly look when underfed — both solved by more light, CO2 and regular ferts. Give this feathery plant the light and nutrients it wants, and it delivers a soft, elegant background few other plants can match.