Making a terrarium
Making a glass terrarium this time of year will help ease the hurt of the past weeks' harsh frosts. They are unique, easy to make, easy to care for, and the live plants give a sense of tranquility. Terrariums are a miniature garden under glass, which need very little care and only a little water added about every month. The water is recycled over and over in the covered glass container.
The materials you need to make a terrarium include:
A glass container with some type of top
Gravel, sea glass or beach stones
Activated charcoal (found at a nursery or pet supply store)
Sterile potting soil with peat, or add peat to the potting soil
Some decorative element (optional)
Look around your home for a glass container. Any glass container will do as long as you can cover it with some type of lid or glass plate, and the container should not have a drain hole in the bottom. A wide mouth container is easier to work with than one with a small mouth opening. However, if the container has a small mouth opening you can use a small long handled spoon or small shovel to plant, and a skewer with a cork on the end to tap down the soil after planting.
When choosing terrarium plants, make sure they are small enough to fit into the terrarium. Their leaves should not touch the sides of the terrarium because they will collect moisture and will rot. Choose plants that like a humid environment and which have low to medium light requirement. An odd number of plants (three, five or seven) is usually more interesting than an even number. The arrangement will be more pleasing if there is a variety of leaf shapes, colors and textures of plants.
While succulents and cactus have a good variety of shapes, colors, and textures, they require an arid climate. If these are what you choose, the terrarium will have to be topless and clean, and coarse sand will need to be added to the potting mixture.
A terrarium does not have a drainage hole in the bottom. To create a place for the extra water to go to keep it away from the plants' roots, place small stones about the size of marbles in the bottom of the container. A layer of sphagnum moss (this is a coarse stringy material) used over, around and throughout the stones will help to soak up extra water.
Next place a 1/4 to 1/2 inch layer of activated charcoal on top of the stones and moss. The charcoal helps with the drainage as well as control any odoer that might occur.
Over the charcoal layer place another layer of sphagnum moss so the potting soil mixture does not filter down and get mixed in with the charcoal and stone layers. This layering will also give the terrarium more aesthetic interest.
The last layer is sterile potting mixture (two-thirds sphagnum peat which is powdery and one-third potting soil). Add as much potting mixture as you can, at least a couple of inches. At this point check to see that the plants will fit into the container with the top on. Before planting the plants, decide how they will be arranged in the terrarium, and if the terrarium will be viewed from one direction or all around. The soil can also be contoured so there are mounds and low areas to create interest.
Use a large spoon or your fingers to dig the holes to plant the plants. Gently pat the soil around each plant to eliminate any air pockets between the roots. If the plants are root bound, gently tease and pull them apart and if needed prune off some of the roots. Pruning will also retard the growth of the plant, a good thing in a terrarium.
A spray bottle works well to water a terrarium. Check the terrarium every couple weeks to see if it needs water. Feel the soil to see if it is dry and add water if it is. The top of the terrarium should be taken off once a month to air out. If there is a lot of condensation or too much water has been added, leave the top off until it has had a chance to dry out. Pull off any leaves that show signs of yellowing or damage, and prune plants that have grown too large. Terrariums never need fertilizer.
Clean the glass sides with a spray bottle and newspaper or paper towels. Glass cleaner may be harmful to the plants.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.