Here's how to take care of common terrarium plants plus how to keep that terrarium clean and looking its best.
To avoid overheating, keep the terrarium in bright but indirect light.
If the terrarium has a lid, it should be able to sustain its own water level with little input, because the water will evaporate from the soil, condense on the inside of the glass and drip down into the soil again. If there is no condensation on the glass, add water by spraying the soil and plants with a spray bottle or gently watering the soil with several tablespoons of water. A well-functioning terrarium will have condensation on about a third of its glass surface. If there's more than that, wipe some away and leave the lid off for a while to allow some moisture to escape.
Water an unlidded terrarium when the top inch of soil feels dry. Water slowly and incrementally to guard against water logging. Terrariums that include cacti and other succulents can be watered even more sparingly.These plants require an unlidded terrarium because they generally resent humidity.
Do not fertilize plants in a terrarium because this may cause them to outgrow the space quickly. Refresh the soil mix annually by spooning out the topmost layer and replacing it with fresh mix.
Remove dead or damaged foliage and flowers regularly, and pinch back plants to encourage bushy growth.
Regularly dust the outside of the terrarium to best show off the plants and so that sufficient light shines through to them.
Image: "Ball terrarium" by Cherus - Own work. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons.
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