How to grow duckweed for your urban pond

Percy Ross once said “Many drops make a bucket, many buckets make a pond, many ponds make a lake, and many lakes make an ocean”. I thought I would start small and grow duckweed in a bucket then move it to a pond. And who knows, my pond may help create more lakes and then flow into the ocean.

Duckweed is a tiny floating water plant that is a really effective water cleanser that pulls nitrogen and phosphates from animal waste and leeched fertilisers and chemicals. It reproduces very quickly and provides a great source of nitrogen for my garden and fish. When grown for a particular function, it becomes a very useful urban water plant.

Duckweed permie checklist:

  • Clean pond water
  • Feed fish
  • Provide nitrogen for biofertilisers, compost and garden
  • Shelter for frogs, fish, snakes, insects and other creatures in the water
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First stages on duckweed production.

Now since my fish (goldfish) love duckweed I couldn’t really grow them in the same pond. So I placed some duckweed in a container with water and a handful of horse manure (nutrition). Filled the container to the top with water and placed it in part sun. I left if sitting there for a week (not much longer as duckweed needs oxygen/aeration) and then “wooallaa”, lots of of duckweed for my pond 🙂 Seven days later, some of the water had evaporated and the duckweed had covered the water surface.

Too much duckweed?

If duckweed is allowed to spread and cover the entire water surface of the pond for long periods of time, it can deplete oxygen resources, block light from underwater plants and eventually kill the plants and fish. So if your pond has too much duckweed just place it directly on your garden as green mulch and/or use it in your compost or biofertliser.

duckweedstagefinal
ONE WEEK later, duckweed is ready for the pond!