Skip to content

Grow Duckweed Year-Round?

October 14, 2014

Now that it’s getting chilly here and winter is drawing closer, the question looms, “Can you grow duckweed year-round?”

I’ve tried it in various small pond to indoor sites and found that it is possible to at least extend the season by a couple of months here in Western Kentucky with nothing more than temporary greenhouse coverings or window sill batches, depending on how much you REALLY want to grow in mid-winter. I usually start up some trays of duckweed under florescent grow lights but have found that natural light does a better job. In a pinch, I’ve done a bit of both- natural daylight supplemented by florescent T-5 or T-8’s.

BTW: T-5’s are more energy efficient than T-8’s, which in turn are more efficient than T-12’s. However, there is a trade-off in terms of sustainability- if you’ve GOT T-12 fixtures and only are going to use them for a few extra hours a day to supplement natural daylight AND can benefit from their use by using them in a living space to light your den, reading nook, etc… then I recommend you continue to use them as is. If you have to go out and purchase fixtures- shoot for the  4 foot long T-8’s with 6500K Daylite bulbs or order T-5’s as you can afford them for best energy conversion. Here is a great read on indoor fixture and bulb selection.

If growing duckweed outdoors in kiddie pools, consider a simple plastic covering, anchored around the perimeter with boards and held up in the center by an upturned cement block in the water. Simple, fast, and while a bit on the ugly side, will extend your season by a month or two at the very least.

If you have a larger open pond, consider letting nature take a rest and coast until spring. Be sure to harvest enough to keep your window sills green and your heart hopeful when the snow is piling up outside. Your goldfish will love you for it.

2 Comments leave one →
  1. Anonymous permalink
    October 15, 2014 11:52 am

    When fall comes to WA State, the duckweed heads for the bottom of the container, and doesn’t stick its head out until well into spring. Even then, it doesn’t multiply much until the sun comes out and the air temps hit 70ºF.

    I gave my neighbor a good handful, and she’s been growing it in elevated 20-gal tubs. Elevated to keep her ducks out of it. But it has stopped multiplying, so I told her to leave it alone until spring.

    Her ducks are so enthusiastic about duckweed (aka ‘duck candy’) she was wondering where she could get some in winter. I told her about this woman in KY who is growing and drying it, and she wonders where she could get some of the dried stuff to feed her duckies in winter.



    • January 31, 2015 11:52 am

      Sue, sorry for the delay. Just saw this. Will be happy to ship your friend some fresh in the late spring. Otherwise, I am sold out of pellets already and am looking to expand production this next summer.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: