How to Build a Terrarium

How to Build a Terrarium

A miniature world under glass, terrariums are fascinating and remarkably easy to create and maintain! Making terrariums can be quick. You can make a terrarium in less than an hour and it doesn't cost much to build one. Terrariums also make unique and thoughtful gifts, even for people who don't have green thumbs.

Here's what you’ll need to build your terrarium:

Glass Terrarium ContainerGlass Terrarium ContainerGlass Container

Your terrarium needs to be large enough to contain plants, decorative elements and some "breathing space." A large jar, fishbowl or shallow glass bowl also work great.

Small Plants: These 1" pots are perfectSmall Plants: These 1" pots are perfectSmall Plants

Mini plants (as opposed to young plants) will not outgrow the size of the container. Be sure to group together plants that have the same sunlight requirements.

GravelGravelGravel for Drainage

Inadequate water drainage is the biggest problem facing mini gardens and terrariums. A layer of small gravel will allow for your terrarium to drain.

Activated CharcoalActivated CharcoalCharcoal

A layer of charcoal will filter the water and help prevent fungi from forming in your terrarium. You'll be glad you added this!

Potting SoilPotting SoilLight Potting Mix

Your soil must maintain the proper balance between water & nutrient retention, and adequate drainage. Mahoney's Premium Potting Mix is perfect.

Decorative ElementsDecorative ElementsDecorative Elements

Think of your terrarium as a miniature landscape - use mini decorative figures such as benches, birdhouses, urns, fairies or even mini-houses. Add moss or rocks for a finished look.

How to build your terrarium

  1. Start off with a bottom layer of gravel,
  2. Add a ¼ inch layer of gardener’s charcoal.
  3. Next, add a layer of soil. Arrange your plants and fill the empty spaces around the roots with soil.
  4. Lastly, you can either do a layer of sphagnum moss or an assortment of other botanicals. I prefer to use lots of different things to add texture, color and visual interest. Some of my many favorites include reindeer moss, lichen, pinecones, pods, river stones and tallow berries. I love talking a stroll through the woods to find some of these mosses, lichen covered branches and interesting stones. A cute little critter nestled in, such as a bird, frog or lizard adds a nice finishing touch. Make sure it is made of resin, stone, or metal so that it doesn’t start rotting or molding over.

If it is necessary to further moisten the container, you may use a turkey baster to add just a bit of water around the edges of the container. After planting, you'll need to observe the container closely until you can tell if the plant is too wet or too dry. If the sides of the container produce too much condensation, you may wish to blot some of the moisture, although a certain amount of condensation is normal, especially during the warmest and coolest parts of the day. Paper towels are great for this job. If you have over-watered a plant you might even take it out of the container and set it on several paper towels. Terrariums are very forgiving, so don't be afraid to remove and add plants as you find the perfect balance.

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