Terrarium Setup with Hydroton and Sphagnum Moss: Good Idea?

A grower asked about placing potted carnivorous plants directly into hydroton clay pellets, covering with live sphagnum moss, and maintaining a water level halfway up the pots to create a large humidity tray.

Why Terrariums Are Often Counterproductive

Christopher advised that most carnivorous plants (Venus flytraps, sundews, Sarracenia, most Nepenthes, butterworts) do not require high humidity and grow well in open pots with ambient humidity (15-30%). Terrariums promote mold, weak leaves, and reduce light penetration. Sarracenia and flytraps need full outdoor sun or very intense artificial light.

When a Terrarium Might Be Needed

Only species with very narrow humidity requirements (e.g., some Heliamphora, woolly sundews, lowland Nepenthes) benefit from controlled environments. For the vast majority, skip the terrarium and focus on light and water.