How to protect your goldfish pond from invasive plants

This is a guest post from Ricky at

Remember how Seymour thought Audrey II was the most amazing plant he’d ever found in Little Shop of Horrors?

If you haven’t seen the film, spoiler alert – the plant starts eating everyone.

Of course, it’s unlikely that invasive plants in your goldfish pond are likely to commit murder! But they could be harmful to your other plants, taking over the living space and restricting their ability to grow and feed.

So, how do you keep these nasties out of your pond?

All about invasive pond plants

Know what you grow

The best way to avoid your goldfish pond transforming into a marsh or bog, is to not put the ‘wrong’ plants in there in the first place. There are some garden centers which will sell plants that might not do your garden any good. Be very careful about what you buy – make sure you know exactly what it is before you take it home, try to plan what you’re going to buy before visiting garden centers and avoid impulse buys.

Here are some particularly pesky plants that you should avoid – and which Plantlife, the organisation that focuses on the welfare of wild flowers, plants and fungi, would like to see banned from sale:

  • Canadian waterweed Elodea canadensis
  • Carolina water-shield/fanwort Cabomba caroliniana
  • Caulerpa taxifolia and Caulerpa racemosa (marine algae/seaweed)
  • Creeping water-primrose Ludwigia peploides
  • Curly waterweed Lagarosiphon major (Elodea crispa)
  • Duck potato Sagittaria latifolia
  • Fallopia japonica x Fallopia sachalinensis
  • False Hampshire-purslane Ludwigia x kentiana
  • Few-flowered leek Allium paradoxum
  • Floating pennywort Hydrocotyle ranunculoides
  • Giant hogweed Heracleum mantegazzianum
  • Giant knotweed Fallopia sachalinensis 
  • Hottentot fig Carpobrotus edulis

Preserve your pond

Left to its own devices, your pond could turn itself into a bog whether there are any invasive plants in there or not. Weed and thin your plants regularly, and make sure that you place the plant waste in your green bin.

Get by without a little help from your friends

We’re not saying for a moment that your friends are trying to sabotage your garden! But if they do offer you any plants be very careful before you introduce them to your pond, especially if your friends don’t know what the plants are.

Battle the invasion

Chances are you’re reading this article because the unthinkable has already happened – your perfect pond has been infested by the dreaded things. So what should you do?

  • Be quick – putting off the job of dealing with the plant will give it more time to spread and establish itself.
  • Get every last bit of the plant that you can find, as it could re-establish itself from a small fragment. To make sure, check again during the following season to make sure it hasn’t started to grow again.
  • If you’re going to clear out a particularly large plant, or a few big ones, consider leaving it until autumn, when your pond and the wildlife in it will be disturbed less.
  • After clearing out any invasive plants, clean your equipment, footwear and clothes thoroughly to ensure that no fragments end up finding their way back to your pond.
  • Don’t forget the frogs! There may be creatures hiding in the plants that you’ve just dug up, so leave it beside the pond for a couple of hours so that any animals can get back to the pond before they end up in the bin.
  • Don’t dispose of invasive plants in the wild, where they could establish themselves and cause a problem for native plants there. Either pop them in your compost bin, or dispose of them using your green bin.

Stay on the right side of the law

Governments are working to stop invasive plants from threatening their native species. In most areas it is a criminal offence to plant, or cause to grow, a non-native invasive species in the wild, so be aware of your local rules and don’t get yourself in trouble.

About the author

My name is Ricky, I am something of a nature lover, I work at Swallow Aquatics (our website is and I enjoy a spot of gardening as well as writing about gardening and the great outdoors. Thanks for reading. 

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