How to make a terrarium

Before you start

Choosing a container

You can buy many different styles of terrarium from simple cubes and glass bowls or jars, to geometric designs or hanging glass domes. Consider bigger or differently shaped terrariums, too. You don't need to buy one – any clear glass bowl or jar could be repurposed into a terrarium. Here's a few ideas for a homemade terrarium:

• Glass globes
• Jam jar
• Closed glass jars with a stopper
• Kilner jar

For more ideas watch our video on choosing a container:

How to make an open terrarium

Topped with a mulch of pale grit and chunky pebbles, the effect is that of a landscape in miniature. Don’t be afraid to play with the top dressing if you want. You could use horticultural sand, or even pecking grit for birds – the grain size is somewhere between gravel and sand – which will add a more naturalistic feel.

Plants for an open terrarium

For an open terrarium choose desert plants that need a drier environment such as cacti, aloes and succulents. Most garden centres will sell a decent range of small cacti and succulents to use in your terrarium.

Five plants for an open terrarium:

• Cacti
• Succulents such as echeveria
• Aloe
• Haworthia
• Peperomia

You will need:

• Cube terrarium
• Free draining compost or cacti compost
• Small cacti, aloes or haworthia
• Grit mulch
• Pebbles

Step 1

Plant a shallow layer of grit in the base of an open container (to avoid humidity building up), followed by a 4-5cm layer of cactus compost.

Step 2

Plant the cacti, using kitchen tongs to handle the very prickly ones. Alternatively, wrap in paper and plant by hand.

Step 3

Using a teaspoon, add a decorative mulch of pale gravel around the cacti. Once the gravel has been added, artfully place several of the pebbles on top. Water sparingly to settle the plants.

How to make a closed terrarium

Closed terrariums should be self sustaining – they create their own ecosystems and become self watering as condensation drips down the inside of the jar. Some closed terrariums may have a narrow neck. If so, you can use a funnel to fill it with compost and long stick to move plants around.Water the plants you are using so they are moist when you put them in to your jar.

Plants for a closed terrarium

Plants that thrive in humidity will enjoy the damp atmosphere of a closed terrarium. These are usually plants that are native to tropical areas such as the nerve plant, ferns or peperomias.

Five plants for a closed terrarium:

• Asparagus fern
• Fittonia (nerve plant)
• Calathea picturata
• Miniature orchid
• African violets

You will need:

• Humidity loving plants
• House plant compost
• Activated charcoal
• Gravel and small pebbles
• Spoon, paintbrush, a cork on a stick, tweezers, funnel
• A sealable glass vessel, with a glass or cork lid

Step 1

Use a funnel to fill a clean dry jar with a 2cm layer of gravel. Add a tablespoon of crushed charcaol on top and spread evenly with a stick or the back of a narrow paint brush. Add 6cm of moist compost to the jar and firm it in using a cork on a stick.

Step 2

Make holes in the compost with your cork stick. Then use a dry paintbrush to wipe down any compost that has stuck to the side of the jar. Remove the plants from their pots.

Step 3

Drop each plant into the jar and use your stick to move each one into a hole. Use the cork to firm down the compost around each plant and level the surface.

Step 4

Tear some moist carpet moss into bits, and push them inside the jar. Firm them into the compost. Drop in the pebbles and level with a cork stuck on to a stick. Seal your jar or bottle.

Next steps

Place closed terrariums away from windows or in a spot where it will get bright, indirect light but not direct sun. Keep an eye on your plants once you’ve made your terrarium and take action if they start to turn brown or wilt.

• How to look after a terrarium