Moss Terrarium Follow Up: Opened or Closed? That Is The Question!

If you remember a few weeks back, 5 weeks exactly, I put together 2 moss terrariums and made a post about them here and here. I had been studying the terrariums very closely to make sure I provided the right environment. About less than a week in, the marimo-moss terrarium had mould growing on the plastic flower so I took them out and decided to leave the container open for a while. While cleaning the container, I noticed the moss looked lush and lighter in colour than the moss in the open container (the one with the dinosaur).

I later replaced the moss in this container with some left overs due to fear of the mould returning. I was very interested in how and why the moss looked different under open and closed conditions so I decided to keep the top-tier open after changing the moss, while the bottom tier remained closed. After 4 weeks, the difference in the two became even more obvious. The moss in the closed container looks lush and filled in or spread out while the moss in the open container looks just like the day I picked them. That is a pretty interesting discovery for me, although I have no idea what it means (I’ve made a few theories thought). Any help is welcome in the comment section. The pictures below are the top and bottom containers that make up the tiered look. The one to the right is the closed container and that to the left is the open container

Moss in open container

Moss in closed container

Side view of open container

Side view of closed container

I kept the dinosaur terrarium open as well. It looks just like the top tier of the marimo-moss tiered terrarium.

Does any one know why the difference in appearance in the two environments? And is the one in the closed container better of than the one in the open container? I am not certain if the lush one is happy or actually crying for help. The leaves of the moss in the closed container looks windswept as if reaching for light, although it is in the same window as the open one.

I am actually surprised I have been able to keep the moss alive for that long. I always thought most indoor moss terrariums were short-lived (for only a few days, certainly not weeks!!) as the terrarium tutorials I read never said exactly how long they last. I stand corrected. I am pretty pleased with it and will see how long I can keep them alive. They are super easy to take care of and thinking of making more as gifts. A lush green moss set up under glass may just be the thing to keep the indoors fresh and looking like spring this winter!.

Till next time!