INSIDE : The best tips on how to care for Marimo Moss Balls! Including where to buy, their watering needs, light needs, the best containers and much more.
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Oh friends, let me introduce you to the newest GREEN pet rock. Every single time I share a glimpse of this new favorite plant, I get tons of questions about what these mystery things in a jar are… drum roll… Today I am sharing all I know about Marimo Moss Balls!
Let’s first start with a ittle bit of backstory on these awesome plants.
Marimo Moss Ball History:
The Japanese word, Marimo, translates to “seaweed ball”. Both Lake Akan, in Japan, and Lake Mývatn, in Iceland, have been declared as national parks and nature reserves to conserve marimo moss, which is a protected species in both countries.
You might be thinking what exactly are Marimo Moss Balls?
Marimo Moss Balls are actually not a “moss” at all, they are actually a rare type of circular algae. There’s no central pit or seed inside the moss ball – it is a solid algae, radiating from the center, growing outward very slowly at about 5mm per year. However, in their natural habitats they’ve been known to grow to between 8 and 12 inches in diameter! Can you imagine having a moss ball that big – how cool.
How long do Moss Balls last?
In Japan, Moss balls are often passed down from generation to generation because they can live up to 100 years! If you take care of yours and change out the water every one to two weeks… be ready for them to live a long time.
How to keep Marimo Balls round:
I have had mine about a year now and have noticed one has slightly lost it’s super round shape. They live naturally in lakes and the gentle waves slowly rotate and roll them around into circles and they form into moss balls.
To ensure that the balls stay keep their round form and don’t flatten out, you’ll want to slightly swirl the water that you have your plant in. When all the balls settle back to the bottom, they will rest on a different side than they had previously. This movement is similar to the gentle waves of a lake. I try to do this once a day as I casually walk past the plant.
Okay, if you are completely intrigued like I was, then you’ll want to know
Where can I buy Marimo Moss Balls?
Oh friends, I am so excited to share that one of my favorite plant store sells these beauties! The Sill is where I got mine… I had to get on a waiting list and then magically one day they emailed they were available. So I RAN and bought three right away. I have been thinking about getting a larger container and adding a few more to the family. The Sill has both mini sized (about 1″) and a regular size (about 2-3″).
Can I have my Moss Balls around fish?
Most fish can live in the same tank with Marimo moss balls. However, a few types of fish and invertebrates may eat or damage the Marimo balls – Goldfish, some types of Plecostomus (Plecos), and large-sized crayfish.
How to Grow Marimo Moss Balls?
For marimo moss to thrive, the container should be kept in a cool place, out of the reach of direct sunlight. To best mimic their natural environment in lakes, the temperature of the water should not be lukewarm to cool.
When you clean change the water, about every two weeks, take out the balls and give them a gentle squeeze in a sink or bucket. You can then put them back in the water.
What is the best container for Moss Balls?
You will be happy to hear there a zillion types of containers that will work for your new plant. I would recommend using a glass sided container so that the moss balls can get light through to the plant. I use these simple glass jars with wooden tops from West Elm, but here is something similar.
I recently found these GORGEOUS round glass vases, I’m getting one right away.
Do Marimo Moss Balls need light?
Keep your moss balls where they will receive low to medium indirect light. You need to protect them from direct sun. Marimo balls can turn brown if they are getting direct light. Marimo do well to even low light spaces like near a normal household light.
How often do I change the water for Marimo Balls:
It is best to change out water once every two weeks using regular tap water. You’ll need to change the water more often in summer, as it will heat and evaporate more quickly. Clean your marimo container with a brush if algae begins to grow on the surface.
Why are my Marimo Balls Floating?
Often times, after you clean our your container and place the moss balls back into the water… they will float along the top of the water. That normally means there is an air bubble trapped inside that is causing them to float. Simple squeeze your moss balls to “pop” the air bubble. They will typically sink to the bottom of their tank within 1-2 days of being added back into the water.
Shop all supplies needed for these amazing plants: