There are many different ways to build a terrarium but if you want to have a happy and healthy one then you need good drainage, a good foundation, and the right conditions for your plants to grow.



Drainage Layer
It's super important to have a drainage layer in your terrarium. This is the bottom layer in a terrarium and allows water to drain off from the soil layer which helps to prevent the terrarium from becoming saturated. A lot of plants don't like wet feet! Gravel, small stones or leca balls are commonly used. I prefer to use small scoria stones in my terrariums - they have a lovely, earthy colour and are porous so they can hold a lot of excess water if I accidentally overwater them.

View our 7mm Scoria Pebbles here.

Charcoal Layer
Charcoal acts like a filter and helps to keep your terrarium clean. It absorbs any toxins that might build up in your terrarium like decaying leaves or mould and mildew. Only a very thin layer is needed to do the job.

View our 5mm Terrarium Charcoal here.

Terrarium Charcoal

Barrier Layer
I love this layer! It prevents the terrarium soil from falling into the drainage layer and coming into contact with any standing water at bottom and basically creating a big mushy mess. There are a few different materials that can be used but I prefer sphagnum moss. Soak it for 1 minute, then squeeze to remove excess moisture and pop in a layer thick enough to keep the soil from washing through into the drainage layer. It also adds some colour to the medium layers of your terrarium. 

Terrarium Soil
This is the most important layer to get right. The plants are going to root directly into it. There are many different terrarium recipes. Here at Flower & Twig, I hand mix a blend of two parts sandy potting mix, one part perlite and one part coco peat.

The potting mix contains nutrients and stability to anchor the plants in place. The perlite helps to aerate the soil so water can pass through, and the coco peat holds onto water that the plant roots can take up when thirsty. It's a simple mix that keeps the plants happy and healthy.

View our Terrarium Soil here.

Now onto the fun part! There are many different plants that will be happy in terrariums. Plant choice depends if you're building an open or closed one. I have a reliable group that I use. Fittonias, Syngoniums and small ferns like Rabbit's Foot Fern or the Crocodile Fern are nice and easy going and look great when planted up.

View our Terrarium Plants here.

Terrarium Plants

Decorative Layer
Let your creative juices flow! There are so may options to choose from. Live moss is amazing in closed terrariums as it loves the environment but it can dry out very quickly in fully open terrariums.
Sand can create an interesting layer - you can also add a few thin layers of different colours. Small bark chips give it an earthy woodland look. These items will protect the roots of the plants, help the roots stay anchored into the soil, and keep moisture in where it is needed most.

All of our complete kits contain 7 different layering materials to help your terrarium get off to the best start and be happy and healthy. 

View our Terrarium Supplies Kit Range here.

You can add small figurines, decorative signs, little sculptures or you can keep it natural looking - it's completely up to you!


 How the layers are placed in a terrarium




  • Hanora said:

    Hi Janice! Hanora here from Flower & Twig. Yes, sometimes the sphagnum moss reshoots over time. I have found that some of my older terrariums have also greened up and it does change the look of the terrarium.

    You’re not doing anything wrong at all, it’s actually a good sign that your terrarium is happy and growing and the moss is loving the environment. Unfortunately it can be hard to know if your sphagnum moss is going to green up as a lot of the time it doesn’t and you won’t know until a few months down the line.

    There are ways to sterilise it further so that it (hopefully) won’t reshoot.

    A common method used to sterilise moss is boiling it.

    1. Bring a pot of water to the boil.
    2. Pop in your sphagnum moss and boil for at least 5 minutes.
    3.Remove from the heat and strain through a colander.
    4. Rinse with cold water and leave to dry out if you are not using it straight away. Never store it damp as it will go mouldy and will smell very bad!

    I hope this helps for your next terrarium build.

    July 27, 2023

  • Janice Schutze said:

    Sphagnum Moss. I have made a couple of terrariums and have used Sphagnum Moss but it shoots, i.e. I get green growth up the side of the jar, from the moss layer, through the potting mix and it continues growing. Is this normal? It spoils the look of the terrarium. What am I doing wrong?

    July 27, 2023

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