Small leaves, a different rhythm
Selaginella offers a finely branching contrast to large leaves and firm rosettes. These are lycophytes, although trade names often use moss or fern. Choose them for foliage texture rather than the wording on a label.
Look at light near the floor
Light at the top of a terrarium can differ greatly from light at the bottom. A branch or growing bromeliad may shade smaller plants. Consider the actual position when planning a green floor.
Moisture without standing water
RHS describes moist, well-drained media for Selaginella martensii. That is a useful balance: avoid complete drying, but do not leave roots in a water-filled pocket. Check the medium before changing watering.
The blue-green sheen
Selaginella uncinata is known for blue-green, iridescent foliage. Its appearance also changes with light and viewing angle. Let it establish and observe new shoots before judging its role in the design.
