Midwest Pond and Koi Society - Q&A #198

Hi Bob:
A friend of mine gave me some water iris a few years ago. They are now taking over my pond. They are a tall iris with a yellow flower and long narrow leaves. I have tried to pull them out but they are woven right into the bottom of the pond.

I would also like to reduce some of the miniature cattails. Any advice on how to do this without harming my fish? The iris have just finished blooming.

Hi Renee!

Omigod, you've got Iris pseudacorus, which, BTW, is kinda illegal in Illinois. It is an invasive, vicious plant pest. What kind of pond do you have? If it's a natural or clay-bottomed pond, just get in there and rip out the giant tubers that are that monster's root system. Get them to dry land, then jump up and down on them until you are sure that they are dead.

It will not be easy and they will fight back.

If your pond is a rubber liner pond, their roots can't penetrate the rubber. Get in there and rip 'em out.

Your fish will love it. Carp love mud and tolerate turbid water just fine. Ripping out the plants will stir up stuff from the bottom that they'll find delicious. DO NOT USE HERBICIDES! You'll kill everything else in there, and the iris will just laugh at you.

Bob