Mason Jar Terrarium

By Kerry Michaels

Updated 11/06/18

DIY mason jar terrarium

Kerry Michaels

Mason jar terrariums make great gifts for teachers, as house presents or to bring to a sick friend. They thrive on neglect so even a determined plant serial killer can keep one of these alive. These terrariums are inexpensive and depending on the plants, can last for years. It takes less than 30 minutes to make.

Making a terrarium in a mason jar is easy, but requires a little finesse because you are working in a very small planting area. While you can make a standard terrarium by planting them right side up, the look of the upside-down jars is very appealing. To do this, you use the lid for your planter. 

What You Need

  • Mason Jars (or any other jar with a screw on lid
  • Small plants
  • Moss (optional)

How to Make a Mason Jar Terrarium

  • First clean and dry your jar. If you use glass cleaner or a harsh soap, make sure to wash out the jar after and let it air out completely.
  • Next, take your jar top and put it on a flat surface, making sure the center disk is securely placed in the lid.
  • Moisten the soil of your plant and then remove its pot or cell, making sure not to pull it out by the top. If it is in a pot, tap the pot and slide the plant out by gently squeezing the sides and tipping it into your hand. If your plant is in a cell pack, squeeze the bottom and push the plant out.
  • If the plant is root bound, rough up the roots either by rubbing them or tearing them at the bottom
  • Squeeze the root ball and then place it in the lid of the jar. You want the root ball to be compact and if possible, have all the roots covered with soil.
  • Press the root ball into the lid so that it is mounded, but doesn't overflow.
  • To give the terrarium a finished look, take small pieces of moss and press them on to the soil around the plant, creating a nice green mound. Keep the moss away from the crown of the plant.
  • Carefully corral the leaves and branches of your plant so they will fit into the jar, being careful to push the leaves and branches up. Gently place the bottle over the plant, using your fingers to push the greenery into the jar. Twisting the jar can help. If possible, keep rotating the jar until the threads of the lid catch. This is a bit tricky and even if you can't make the threads catch, you can rest the lip on the jar on the lid and create a seal. Just be careful to remember this when moving the jar and pick it up by the lid and the glass.
  • To care for your terrarium, keep it out of direct sunlight, but try to give it bright indirect light. You may not have to water it for months, though you should check to make sure the soil is moist, not wet every couple of weeks. If you see lots of condensation on the jar, leave it open for a few hours to dry the soil out a bit.
  • I've used pansies for this terrarium, but you can use any small plant that will survive with indirect sun. Click here for a list of great terrarium plants.

    To add a whimsical or decorative touch to your terrarium, place stones, shells, miniature figurines or anything else that will survive the humid atmosphere of a terrarium. Make "memory" terrariums by collecting and add keepsakes from a vacation, and create a terrarium with those as the theme. To give as a gift, simply tie a ribbon or piece of raffia around the lid of the mason jar.