INTRODUCTION:

A terrarium is a garden of plants growing in a clear container, such as a bottle, glass globe, old aquarium, carboy, or similar object. The terrarium can be landscaped to represent a scene in nature, a miniature ecosystem. The plants used in a terrarium should be compatible and cultivars that stay small or grow very slowly. The medium should be well drained, but hold adequate moisture and should not be very fertile, since a fertile medium would tend to encourage rapid growth. If the container has a small opening or is to be closed, the plants must be able to tolerate high humidity.

OBJECTIVES:

The objective of this activity is to learn the basic techniques of making a terrarium.

 

ACTIVITY:

The activity of this lab is to make a terrarium similar to the one shown in the diagram below.

 

MATERIALS:

Clear bottle gravel charcoal
peatlite mix water label
Miniature cultivars of tropical plants that survive in low light and high humidity

 

PROCEDURES:

Choose a glass container for the terrarium. This may be one of the containers provided in lab or your own decorative container. Put a 1/2 to 1 inch layer of gravel into the container. Add one to two tablespoons of charcoal to the gravel layer. Then fill the container to about 1/4 its depth with peatlite mix.

Choose a group of compatible plants for the bottle garden. Usually this would be three to five plants, three in the smaller sized containers and as many a five for larger container. The plants should all be able to survive in a humid environment with reduced light. Choose plants that have varied characteristics, for example one that will be taller than the others and one that will be low and spreading in growth habit. Choose plants with varied leaf textures, shapes and colors. Choose one plant for its specimen quality, for example a plant that will flower in the terrarium

Inspect the plants before putting them in the terrarium. Check for pests and control them if present. Remove old, yellowing leaves, dead flowers and other unwanted plant material. If the plant is a little too large for the container, prune some of its leaves and/or stems so that it will fit.

Set the plants in the terrarium in an aesthetically pleasing arrangement. The tallest plant should go in first, then the intermediate plants and finally the smallest plants. DoníŽt crowd the terrarium, save space for the plants to grow! Cuttings or newly rooted cuttings are excellent for planting a terrarium. If you use potted plants, remove most of the potting medium from the root system. Prune long roots that will not easily fit into the medium. It is better to prune these long roots than to mat them into a pile and cover them with medium. Remember that the terrarium is an excellent place for root development since there is very little stress on the plants.

Stand back and look at our terrarium from a distance to be sure that it is aesthetically pleasing. This is often difficult to tell when looking at it from above. When you are convinced that the placement of plants is proper, water the terrarium. Since the peatlite mix will hold a lot of water, add the water in increments to avoid overwatering. In general you would add a volume of water equivalent to one-fourth to one-third the volume of the medium in the container.

You may want to put ornamentation in your terrarium. A path may be made of gravel or stones, driftwood could give the appearance of a decaying log and rocks or petrified wood could be used to represent rocks or hills. Avoid artificial flowers and artificially colored stones or pebbles. Small artificial reptiles, birds and other critters are acceptable, but only with natural coloring.

When you have finished the terrarium, label it with your name and date and place it under the lights in the light bank in our lab room. Once the plants are well established in their new environment, you may take the terrarium home, but check with your lab instructor before taking it.

LINKS:

Constructing and Maintaining a Dish Garden

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