Zebra mussels (Dreissena polymorpha) are affecting one of our favorite houseplants? Did you know?Maybe you did, as it has been a problem for over two years. I didn’t know.

What houseplant is it affecting? The adorable Marimo moss ball. I do have many of them, but they are old, so this problem doesn’t apply to my plants. (Actually it is an algae.)

I guess because I haven’t bought one lately, it hasn’t been on my radar. But, when I was at the pet shop a while ago, looking at the plants, I thought having another moss ball wouldn’t be a bad idea. They told me then I couldn’t get one because of the zebra mussels. So I looked into it.

What are zebra mussels?

Zebra mussels (Dreissena polymorpha) are small bivalve shellfish that live in freshwater. They are small and have stripes like zebras. (Sorry I don’t have a picture.) They are an invasive species in the Great Lakes, and in other bodies of fresh water in the United States.

Zebra mussels are filter feeders and siphon parts of plankton from the water. This takes food sources from native species. They attach themselves to hard surfaces such as boat hulls and pipes and they are almost impossible to control. At this point, they are trying to prevent the spread.

Zebra mussels and Marimo

What do zebra mussels have to do with Marimo balls? These invasive creatures were discovered on a Marimo ball in a Seattle pet store in March of 2021. Their care involves changing the water and emptying it in our sinks. The zebra mussels, if present, could then cause problems.

Because they of the ban in some states, most pet stores don’t sell them anymore. I called many pet stores to see if after two years they had them back in. Only one pet store out of the 7 I called had them for sale. Are they supposed to sell them? I’m not sure.

UPDATE: I bought one in a Michigan pet store last week. I felt good with that decision after talking to Luke Nathan from the Michigan Fisheries Division. He did confirm that Marimo are legal to sell in pet stores in Michigan. They just ask people to be on the look out for the mussels.

The other store’s employees did say they are hoping to see them come back. They were a popular item. Who doesn’t love them?

Marimo destruction

How will you know if you have an infested marimo? If you bought your marimo after February of 2021, it may be infested. You would probably know by now as it has been a couple of years.

State and federal goverment invasive species agencies asked that if you had purchased a marimo after Feb. 2021 to destroy it. How heartbreaking….

How do you destroy it?

From what I found, there are three ways to destroy your marimo and prevent the zebra mussels from spreading. You can freeze it for 24 hours, boil it for one minute, or soak in bleach for 10 minutes or vinegar for 20 minutes. Then put it in a sealed plastic bag and place in the trash. Problem gone.

Is there a replacement for marimo balls?

I don’t think there could be a replacement for the adorable marimo. But, after visiting Petsmart this week, I found they do have moss plants. There aren’t in any way like a marimo. Marimo are algae, but most people assume they are a moss.

These moss, for which have no identification, are flat green disks. These are not cute like a marimo, but they are green and in a round shape….. I bought one and will see what it does. I’m assuming it will continue to be a round disc of green.

I am so glad I bought my Marimo balls long before 2021. I hope you have an old one, too. If you do, make sure to keep them healthy, as you may never be able to buy one again. I love these little green algae balls and am glad I have them.

Have a great week, plant friends.