Leucobryum glaucum (Pincushion Moss / Pillow Moss) Made Easy

Pincushion Moss is a true terrarium staple.

Seriously. I rarely build a terrarium without it. It would be like Christmas without turkey! 

Immediately recognizable by its lush green mounds – hence the many cushion-based names – Leucobryum glaucum is a welcome addition to any project. 

Honestly, with such fluffy verdant texture, there’s no easier way to bring a terrarium to life. Placing just a few of these clumps can instantly transform a landscape from boring to vibrant. 

Easy to care for, stunning, and versatile – is this the pièce de résistance of terrariums and vivariums?

Let’s find out.

Whether you know it as Cushion Moss, Bun Moss, Pincushion Moss, or Pillow Moss, one thing we can all agree on is that Leucobryum glaucum is one of a kind.

It’s actually a temperate moss found in woodland and wetlands areas around the world. But don’t let that fool you; it performs better in tropical terrariums than most tropical mosses.

That’s because of its incredible adaptability and versatility.

Being an acrocarpous moss, it doesn’t branch out and instead grows in very compact ‘clumps.’ Making it perfect for terrariums of all shapes and sizes.

For starters:

• It’s never going to outgrow a space – As they mature, they don’t get much bigger; their leaves just seem to flesh out a little.
• You can tear it apart to create perfectly sized clumps – Whether you need a large mound or just a button-sized amount to fill a space, you can create exactly what you need.
• It’s super easy to place and sculpt – The chunks of moss are much more manageable to intentionally set than their sheet moss counterparts. Allowing you to make a seamless mossy landscape.

Honestly, what’s not to love?

See the links below to purchase from reputable terrarium plant shops and marketplaces (may include affiliate links). 

Lighting

While Pillow Moss can tolerate a low-light terrarium environment, it really needs a bit more sunlight to truly thrive. More so than other popular mosses – so I’d aim for the gold standard: bright, indirect light.

For those of you in the Northern Hemisphere, a North-facing or East-facing windowsill is perfect. On the flip side, if you live in the Southern Hemisphere, opt for a South-facing or West-facing windowsill.

Ultimately, see what works, try it out in a few locations, and don’t hesitate to supplement with a grow light if need be.

One thing to note, Pillow Moss does best when kept out of direct sunlight. Which is handy when almost every terrarium plant prefers indirect light, too. 

It can tolerate a little direct light, so I wouldn’t worry if it gets a few hours here or there.

Watering

This temperate, spongy moss thrives in moisture-rich environments. 

So, for best results, you’ll want to keep it consistently moist but not completely saturated. 

As you’d expect from a sponge, Leucobryum glaucum retains water incredibly well, too. Which is excellent for boosting humidity in a terrarium, but it also means it can be easily overwatered if you’re pouring rather than spraying/misting.

I find the easiest way to get started is to soak your Pincushion Moss in water until it’s fully rehydrated and then squeeze out all of the excess moisture.

In a high-humidity closed terrarium, that should be plenty to keep it going for a long while!

When it does need a top-up, a light misting with a spray bottle is all it takes.

Substrate / Soil

Moss doesn’t have any roots, right?

So, the substrate choice isn’t super crucial like it is for plants.

In the end, your Cushion Moss is going to get most of its moisture from the air and direct watering. So you can be confident that your moss will grow fine on whichever terrarium substrate you choose.

That said, if you’re pairing your moss with other terrarium plants, our signature terrarium substrate mix is a good, balanced option.

Pro tip: It does have tiny root-like structures called “rhizoids” on the bottom, so it can be helpful to press Cushion Moss down a little to anchor to the substrate.

Temperature & Humidity

Pincushion Moss is an incredibly adaptable species.

Thanks to its temperate nature, it’ll happily grow at a typical room temperature range of 65-80°F (18-26°C).

Humidity is more critical, so you’ll definitely need a closed container for this one. The higher the humidity, the better, as it can quickly dry out if exposed to dry air. 

Thankfully, most closed terrariums can easily reach 90%+ humidity. 

That being said, If you’ve pre-soaked your moss, it’ll probably manage to retain its moisture even in lower humidity levels. You’ll just need to mist it more frequently.

Growth

Though Pillow Moss can grow to be quite large in the wild, they barely seem to grow at all in terrariums.

You’ll notice that they tend to grow longer and bushier rather than broader or taller.

So, you don’t need to worry about your little fluff ball becoming one of those outdoor giants (or outgrowing your terrarium/mossarium). But it might need pruning occasionally.

A little off the top should be all that’s required.

Pincushion Moss Propagation

Unlike carpeting mosses, you won’t be able to propagate Pincushion Moss through division.

Instead, new plants form at the edges of each tuft, which then fall off and form new cushion colonies.

Cushion colonies, how adorable…

Though I can’t say, I’ve seen much of this occurring in my terrarium projects.

Varieties & Similar Plants – Cushion Moss Vs Mood Moss

Typically when people mention Cushion Moss, they’re referring to Leucobryum glaucum.

But if we’re being technical, it’s actually more of an umbrella term, encompassing any of the Leucobryum genus that forms ‘clumps.’ 

This includes Leucobryum juniperoideum – glaucum‘s lesser-known little sister – which tends to form much smaller clumps with much shorter leaves (also known as phyllids… the more you know).

Cushion Moss often gets confused with Mood Moss – Dicranum scoparium. They’re by far the two most popular and commercially available clumpy mosses on the market.

It’s extremely luscious, long, and fluffy, and the two go together like peanut butter and jelly.

> See our Terrarium Moss Guide for more great moss species!

Frequently Asked Questions