How to make your own terrarium

Enclosed in their glass structures, terrariums are as popular now as they ever have been. Whether you fill your house with them or just have a few well-placed arrangements, terrariums can bring a fresh look to your interior, making them an effortless way to give your home an update. Here’s how to unleash your green-fingered creativity and make your own…

When arranged in the right way, plants can bring order to a room, helping to bring nature into your home while highlighting aesthetic features such as shelves, window cills, and bathroom ledges. 

Terrariums are miniature gardens grown within a transparent container – usually glass, resin, or plastic – which acts like a greenhouse. They are the ultimate self-sufficient, low-maintenance option for people who have little time to care for houseplants, or for those who have a tendency to over-water them! Inside a terrarium, the plants naturally emit water vapour as they grow, which collects on the walls of the container and then trickles back down to the soil – making them self-watering.

From accidental beginnings

Although they have been a highly successful trend in recent years, terrariums are a part of our past and have been a popular feature in our homes since the 1800s. They are first mentioned in a botanical book called ‘On the Growth of Plants in Closely Glazed Cases‘ by natural scientist Nathaniel Bagshaw Ward in 1852. In the book, Ward explains that he unintentionally developed the concept during an experiment that studied an insect emerging from a chrysalis. He had placed his small subject into a wide-mouthed glass bottle with some soil and mould, and noted that moisture was being drawn to the top of the bottle during the day. 

Quite unexpectedly, he managed to sprout a fern seedling in the glass bottle; something he had been struggling to do outside in his garden. The little fern managed to grow happily in the bottle for four years without watering, which was considered to be quite remarkable at a time when people were fascinated with exotic plants. While Ward originally concluded that the fern’s success was due to the glass protecting it from the pollution in the air, he went on to devise more glass cases and soon developed the concept to the point where ‘Wardian Cases’ were a common sight in any Victorian household. 

Ideal for orangeries or garden rooms

In an extension such as an orangery or garden room, a terrarium can make a very striking feature; helping to complement the glazed walls and emphasising the differences between the larger and smaller glass structures. They can make wonderful centrepieces on long family dining tables, highlight different ends of a shelving unit or frame the centre of a smart kitchen island – the opportunities are endless! They can draw the eye to specific areas in the room, soften straight lines and can help to create a stronger link with the garden beyond. 

Gone are the days of overheated conservatories; modern-day orangeries and garden rooms now have outstanding temperature control features – but if you like the idea of keeping exotic plants in yours just like the Victorians used to do, then terrariums are ideal for growing species that like very warm or humid conditions. 

How to make your own terrarium

You will need:

• A glass container – let your imagination run wild, anything can be used as long as it creates the same self-watering effect. 
• Activated charcoal – you won’t need very much, but a layer of this will help to keep bacteria out of your terrarium. 
• Small digging tools (a spoon is more than suitable), tongs, and a funnel. 
• Drainage – traditionally, these are usually small pebbles, rocks or gravel but again, be as creative as you like – there is a range of colours and materials to choose from. You will need a larger and smaller size grade inside your terrarium.
• Potting soil – you can purchase specialised mixes depending on your choice of plants. 
• Small plants and succulents of your choice – choose plants that will do well in high humidity, such as succulents, cacti, and ferns. Select varieties that will thrive in lots of sunlight. 
• Decorative ornaments – here’s another opportunity to be creative; use anything you like from vintage teacups, small figurines, shells, crystals, dried driftwood, or fairy lights. Adding a pumpkin or a Christmas snowflake can make very unique seasonal terrariums for parties. 

Method:

• Wash the container and stones with hot water and a mild soap detergent; rinse well. 
• Cover the bottom of your terrarium with sand, as thick as you need depending on the size of your container. You can layer different colours to make patterns, or stick to one neutral shade – the funnel can help you to build up thicker levels in different parts of the container. 
• Cover the sand with the smaller pebbles first, then the larger stones. The bottom layer of small pebbles will act as drainage for your terrarium.
• Add a thin layer of activated charcoal, before putting in a layer of soil. You’ll want to add enough potting soil so that it’s deep enough for your plants to root into it. We recommend a 2 ½ inch layer.
• Now begin planting; start with the larger plants first, and work from the back to the front of your glass container. Remove the plant from its pot, trim the roots if required, and nestle into a hole in the soil. 
• Once all of your plants are in, finish your terrarium with an additional layer of the smaller pebbles and add your decorative ornaments. 
• Place your finished terrarium in a well-lit spot, and lightly water the plants every two weeks. If you have opted for a classic sealed terrarium, then it will require even less watering – keep an eye on the soil now and then to make sure that the environment inside the glass has not dried out.