Terrarium Planting Checklist

Choose open or closed before buying plants

A closed terrarium holds moisture under a lid. An open display exchanges air with the room and usually dries more quickly. Choose the plants and container together. A dry-growing cactus and a moisture-loving fern do not make a good shared planting.

Small ferns, fittonia and other compact plants suited to humid conditions can work in a closed display. Check the variety's mature size and care label. Use small, healthy plants with room to grow; reject plants with pests, damaged roots or extensive yellowing.

Penn State's closed-terrarium instructions explain plant selection, clean containers and moisture control. Keep a closed container out of direct sunlight, where heat can build up. A bright room or indirect light should still match the plants you choose.

A terrarium is a display for suitably small plants. A clove tree is a tree, not a permanent bottle-garden plant. Grow a tree in an appropriately sized conventional container and move it to larger accommodation as it grows.

Make a terrarium, step by step

Gather a clear container, suitable container potting mix, small plants, a spoon or narrow trowel, clean scissors and a way to add a little water at a time. A wide opening makes planting and later pruning easier. Clear glass or plastic lets light reach the plants.

1. Clean the container. Wash and rinse it well, then let it dry. Clean tools and any decorative stones too. Keep cleaning-product residue away from the plants.
2. Prepare the mix. Use an appropriate container mix rather than digging soil from the garden. Moisten it lightly before planting; it should not be dripping wet. Different plant groups need different media, so follow the plants' requirements.
3. Plan the view. Arrange the nursery pots on the table first. If you will look through one side of the glass, place taller plants toward the back. Leave room for the small plants and for your tools.
4. Add enough growing medium. Allow for the depth of the chosen root balls. A decorative gravel layer may collect excess water, but a jar without a drain hole cannot discharge that water. Gravel is not a reason to water more.
5. Plant gently. Remove nursery pots and set the roots into small pockets. Keep each plant at its previous growing depth and firm the mix lightly. Leave foliage clear of the glass where possible.
6. Finish with a small amount of water. Settle the mix without leaving standing water. Clean loose mix from the leaves and glass. If foliage is wet, let it dry before putting on the lid.

Iowa State's terrarium guide covers containers, planting and ongoing care. Its gravel layer is a place for excess water to collect inside the container; it is not an outlet. Choose an ordinary pot with drain holes when a plant needs a thorough watering and free drainage.

Our potting-media ingredient table explains the roles of bark, coir and mineral ingredients. It is a reference for selecting media, not a universal terrarium recipe.

Water and care for the display

Watch the display closely in its first days. Some condensation in a closed terrarium is expected. If the glass stays heavily wet or water pools below the mix, remove the lid and let conditions dry before closing it again. Keep the terrarium out of a direct sunbeam.

Check the growing medium and plants together. Dry mix, a change in condensation and wilting are clues to investigate, not a reason to pour in a set dose on a weekly schedule. Add a little water only when needed. An open display may need attention sooner than a closed one.

Remove shed leaves before they decay. Trim growth that crowds the other plants or presses against the glass. If a plant becomes too large, transplant it rather than repeatedly forcing it back into a tiny space. Use the added-check feature to record a reminder for the particular plants you chose.

Solve common terrarium problems