Arundo donax (giant reed): what is it, and should it be planted near a pond?

Four- or five-metre stems, blue-green foliage that rustles in the slightest breeze, the appearance of a Mediterranean bamboo: giant reed rarely wins everyone over, but it never leaves anyone indifferent. Arundo donax is a giant rhizomatous grass, magnificent as a specimen plant but very vigorous, classified among the world's most invasive plants in warm regions. Near a pond, it therefore calls for careful consideration.

Giant reed identification card

Its hollow, rigid stems have been used since Antiquity: for stakes, screens, windbreaks, and above all reeds for wind instruments. Clarinet, saxophone, oboe and bassoon reeds are traditionally made from Arundo donax. More recently, its very rapid growth has made it a candidate for biomass production.

An invasive plant, especially in the south

In our regions, giant reed rarely produces viable seeds and spreads almost exclusively through vegetative propagation. That is where the problem lies: the smallest fragment of rhizome or stem carried away by a flood can take root farther downstream. Along Mediterranean rivers, in California and Australia, it forms dense stands that smother native vegetation, and it is listed among the world's 100 most problematic invasive species by the IUCN.

To our knowledge, it is not currently on the list of species of concern to the Union under European Regulation 1143/2014, so its cultivation is not prohibited in Belgium or France. This list is regularly updated: check it before planting. And regardless of its legal status, never plant it beside a watercourse, ditch, or pond connected to a stream.

Can it withstand our winters?

In Belgium and northern France, giant reed grows, but more slowly than in the sunny south. The stems can freeze during harsh winters; the rhizome generally survives in soil that does not remain waterlogged all winter and starts growing again in spring. The variegated form, « Versicolor », is more decorative, less vigorous, and distinctly more tender.

Why be cautious near a pond

• Liner: thick rhizomes and pointed shoots exert strong pressure. Planted in the soil against a liner, giant reed can deform, lift, or damage it.
• Invasiveness: within a few years, a clump can colonize several metres of bank and become very difficult to remove.
• Leaves: in autumn and winter, dry leaves fall into the water in large quantities and feed the sludge.
• Shade: at 4 m tall, it can shade a large part of a small pond.

If you still want to plant it

1. Plant it a safe distance from the liner, in the background, never in the bank itself.
2. Surround the pit with a rigid rhizome barrier, buried deeply and extending slightly above the ground.
3. Or grow it in a large above-ground container, the safest solution.
4. Cut the dry stems at the end of winter and never throw fragments into the wild or into the compost of a damp garden.

Alternatives for the edges of a pond

For a vertical effect at the water's edge without the drawbacks of giant reed, consider native marginal plants grown in baskets: yellow flag iris, rushes, lesser bulrush, sedges. They filter the water, shelter dragonflies, and remain easy to contain. At the surface, a floating island adds height and volume without touching the liner.

Read also

To contain your marginal plants: Use perforated baskets rather than traditional pots for your aquatic plants.

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Frequently asked questions

— Is Arundo donax a bamboo?

No. It looks similar, but it belongs to a different grass subfamily than bamboos. Its broad leaves sheath the stem directly, without the short pseudopetiole characteristic of bamboo leaves.

— Can giant reed be planted in water?

No. It tolerates waterlogged soil and temporary flooding, but not permanent immersion like a true aquatic plant.

— How do you get rid of giant reed?

By completely removing the rhizomes, often with a mini-excavator, followed by repeated cutting of new shoots for one or two seasons. The waste must be disposed of without risk of spreading.

— Is it banned in Belgium?

To our knowledge, no, but it is recognized as invasive in many warm regions. Plant it far from any watercourse.

In summary

• Arundo donax is a giant rhizomatous grass, often 3 to 5 m tall.
• It spreads through fragments and is highly invasive in warm climates.
• It is not an aquatic plant and can damage a pond liner.
• If you plant it: away from the pond, with a rhizome barrier or in a container.
• At the water's edge, choose native marginal plants in baskets.

Last updated: September 28, 2026.