What aquatic and semi aquatic plants would you recommend to plant in and around the edge of a pond in order to help clean and filter the water?

Question:

We have two ducks and to keep them happy and healthy, this winter I dug out a small pond for them. The pond is approximately 10′ by 18′ with varying depths of 12 to 30+ inches. It’s in a naturally low lying area that tends to be wet for a good part of the spring anyway, with marine clay soil…hence the area is not really draining well. To keep the side walls supported I lined the pond with black filter fabric and then placed rocks over it to hold it in place and create a gravelly bottom. No rubber liner needed…the pond is holding water just fine. My question is: what aquatic and semi aquatic plants would you recommend to plant in and around the edge of this pond, in order to help clean and filter the water, and where can I source them from?

Answer:

Jonathan Foster, Home Horticulture Outreach Professional

What a fun and interesting project you have going.

Unfortunately, we don’t have anyone highly experienced with aquatic plants in such a setting, and most of the extended Extension resources I consulted are focused on control of problematic species in pond management. I did, however, find this page from the Iowa State Univ Extension on aquatic plants for water gardens–I know it isn’t quite the same scale as your duck pond, but it has some good advice and (more importantly) plant lists. The Lake Stewards of Maine also maintains this key to common native Maine aquatic plants, which you should find a useful resource to consult, as well.

Be sure to compare any potential purchases to the State of Maine’s Do Not Sell list for problematic aquatic plants, just to make sure you don’t introduce anything invasive.

I’m sorry not to be able to give you more specific advice, but I wish you good luck and happy gardening.