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Quick Plant Care Guides How to Grow Duckweed Lemna

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Quick Plant Care Guides. Plant care, simple and to the point.

Duckweed is for Homesteading

If you have a homestead, livestock, or even a simple garden; growing duckweed can play an important role in your success. Duckweed is one of the best permaculture plants you can grow. Keep reading to find out why!

Various Duckweed Species in a Pond

Duckweed and Amazon Frogbit in Pond

Duckweed and Amazon Frogbit in Pond

What Do You Think about Duckweed?

Why Grow Duckweed?

Fast, Sustainable Growth

Duckweed grows FAST. A useful, fast-growing plant is A+ for the sustainable homestead. As a permaculture plant, duckweed is a must have species.

You can toss a couple shovelfuls of manure in a small duckweed pond and that is usually all the plant needs to grow its best.

  • If you over do the poo, you will have a stinking mess. Go easy on fertilizing until you find the right balance.

It is a heavy-feeder and will use up a lot of nutrients in its pond. Even though you're feeding it valuable manure (or whatever), it creates so much easy fertilizer as a mulch/compost, its worth it.

Livestock Feed

Duckweed can be used as a feed for goldfish, tilapia, chickens, turkeys, ducks, even mammals.

Ducks eat it wet, right out of the water. You can serve it to them in troughs, if they are kept in pens.

My chickens eat it wet or dry out of a pan.

I have never fed it to mammals but people do.

Yes, people. People can eat CLEAN duckweed. (I've never tried it, seems dubious!)

Duckweed in the Garden

This is where duckweed shines on my little homestead.

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Duckweed makes a great mulch in your garden. It keeps weeds down and quickly rots away to feed your plants and worms. I use it wet and dry in my gardens. A layer three or four inches thick really works well. I don't put it up against plant stems. I usually keep it a few inches away from the actual plant.

You can add as much duckweed as you want to your compost pile. Just add your brown matter as you normally would for the amount of green duckweed.

I toss it on my red wigglers (earth worms) and they enjoy eating it, as well.

Throwing massive amounts in your chicken coop will let your chickens turn it into a chicken manure additive for your gardens. Just toss the finished product on your compost pile, in the worms bins, and around corn and trees. Avoid using raw manure on most of your edible plants.

Duckweed in Aquaponics

Duckweed is used to purify water running from your other plants and into your fish vats in aquaponics.

I use it in my aquaponic setup to keep the water safe for my fish and invertebrates.

Duckweed is Easy to Grow

Amazon Frogbit (Limnobium laevigatum) and an Unfortunate Moth

Amazon Frogbit (Limnobium laevigatum) and an Unfortunate Moth

How to Grow Duckweed


Duckweed prefers non-flowing water.

A large surface area and plenty of sun helps you grow the most duckweed.

Make a Small Duckweed Pond

For small amounts, use a plastic kiddy pool, in full sun. Add a shovel of manure and fill with water. Toss in a few duckweed starts and away they go.

If your plants start to slow down and you begin to see some yellowing, it is time to feed again.

Make a Large Duckweed Pond

A larger homestead or permaculture farm, requires more duckweed.

If you have a natural pond already in place, you can easily grow duckweed there. Just toss some in and you won't even have to feed the plants.

Putting in a large duckweed pond can be as simple as a shallow, two foot deep lined area. Make the pond at least four feet wide. It can be as long as you want.

Discarded above ground pool liners, pond liners, or cement can be used to line the pond. If it holds water and is non-toxic, you can grow duckweed in it.

Rectangular and long ponds are easier to harvest from. You start at one end and sweep the duckweed towards the other end. Use rakes or nets when harvesting duckweed plants.

Duckweed doesn't need deep water, but the deeper your pond is, the more time you have before it evaporates or needs topping off.

Duckweed is Persistent

I forgot duckweed in a bowl that mostly dried out over the course of over a week. The top layer is dead, the bottom is still alive.

I forgot duckweed in a bowl that mostly dried out over the course of over a week. The top layer is dead, the bottom is still alive.

Prevent Mosquitoes In your Duckweed Pond

  • Kiddy pools can be covered with row cover fabric. Mosquitoes cannot lay eggs through it.
  • Narrow, rectangular ponds are easily covered in row cover fabric. The cover allows light in for the plants but helps keep mosquitoes to a dull roar.
  • Mosquito Fish (Gambusia affinis) do well in kiddy pools and large ponds. These tiny live-bearers are tops at keeping pesky mosquitoes at an acceptable level.
  • You can also use mosquito dunks.

Duckweed Can Kill your Ponds

Never let duckweed cover your pond completely. (unless it is a pond JUST for duckweed)

The reason duckweed works for me on my organic farm is because I manage it. I use it as soon as it is ready to harvest. If you stop harvesting your duckweed, it WILL take over a pond and smother the life beneath it.

Stocking goldfish can help keep the duckweed in check, but I wouldn't rely on goldfish to do it, just in case.

To prevent your goldfish from taking over your pond, try stocking only males OR females. This will require you to sex them. It isn't all that hard but can be tedious.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2019 Isadora


Isadora (author) from Tennessee on August 02, 2019:

Thank you! I love me some duckweed!

The Logician from then to now on on August 02, 2019:

Awesome information! Thanks,

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