Terrariums are made up of layers of different growing materials. To assist with drainage (because terrariums don’t have any drainage holes), gravel or perlite is usually laid in the base of the vessel.
Horticultural charcoal is spread on top of the gravel and this helps remove the sour smell of wet potting mix. Sphagnum moss is next, and this helps the final layer of peat moss or potting mix retain moisture. However, the combination and type of material can vary depending on the plants you choose.
Indoor plants like African violets and hypoestes grow best in this combination, whereas succulents and cacti prefer a more free-draining mix like sand, and require less moisture-retentive material, so can do without the sphagnum moss. Before you start, consider what plants you will be using – this will determine the type of material you use in your terrarium.
What to plant
Plants that thrive indoors grow best in a terrarium. Choose and group plants with similar lighting needs and growing conditions.
• Succulents
• Cacti
• African violets
• Baby’s tears
• Small ferns
• Hypoestes
• Fittonia
• Sansevieria
Care and watering
• A gentle weekly mist is sufficient watering. It is always better to under-water than overwater, as it is difficult to remove excess moisture.
• Position in a brightly lit spot, such as near a window, but not in direct sunlight. Occasionally rotate the vessel to make sure plant growth is even.
• Keep the container clean by removing dust or moisture from the glass. Also, remove any dead leaves to prevent growth of fungi.