1. PUTTING THE TERRARIUM IN THE WRONG PLACE
Keeping the terrarium in the right spot is important, so be sure yours will fit in the position you have in mind when planning your design. Closed terrariums prefer bright, indirect light, while open ones like a well-lit spot that's not in direct sunlight. Again check out the requirements of the plants you have in mind.
2. WATERING YOUR TERRARIUM INCORRECTLY
When it comes to watering plants in terrariums it depends on how many plants you have included in your scheme and what type they are, as well as whether or not your terrarium is an open or closed design. Remember also that terrariums retain water for longer than most other houseplants.
3. FAILING TO TRIM TERRARIUM PLANTS
Pruning terrarium plants can be tricky due to the enclosed nature of the space and density of planting. You will need to trim back any plants that touch the sides of the terrarium or have grown so tall they are reaching the top. It's worth investing in a special set of extra long aquarium tools (available from Amazon) including scissors and tweezers that are perfect for the job.
4. LETTING THE TERRARIUM GLASS GET DIRTY
If the glass is too dirty or foggy, it will prevent light from reaching your plants which can be detrimental to their health. Regularly dusting the outside is an important part of terrarium care as this allows light in, as well as showing off your plants. Either moisten a paper towel or use a soft clean cloth to simply wipe the glass. Avoid using glass cleaners as these may container chemicals that will be detrimental to your plants. When cleaning the inside of the terrarium use distilled water or better still collected rainwater with a soft lint-free cloth. You only need the tiniest amount of water. Do not use a cleaning solution as that could contain chemicals that might be harmful to plants. While you're there, don't forget to clean houseplants in your terrarium too.
5. FAILING TO ACT QUICKLY IF THE TERRARIUM GETS BUGS
If you have an open terrarium, monitor regularly for pests as part of your terrarium care. 'Gnats, mites, and mealybugs are all known plant parasites that can hitch a ride into terrariums via plants and substrate,' explains plant expert Dan Jones of Terrarium Tribe.
If you think there's a problem take action immediately. Plants for terrariums aren't expensive and keeping a plant with an infestation in a terrarium means it could easily spread to other plants.