Terrariums, Part II
In my last column, I discussed the history of terrariums, and a few factors in selecting a terrarium and preparing the bed.
When you select plants, several things must be kept in mind. First is plant height. Although taller plants can be trimmed back, this will require more work on your part, so shorter plants will work better. Light requirements must also be considered. Some plants require more light than others do. It is important to remember that the closed container can never be placed in direct sunlight, since it would "cook" the plants. You must also evaluate the plant's humidity toleration. A closed container will provide a humid environment, so the plant must be suitable. Finally, the temperature requirement of the plant must be met. Some like warmer temperatures, others prefer cooler.
Since you will probably want more than one kind of plant, you will have to consider all these factors for each plant you want to include. Make sure that all of the plants you select will work together for the conditions that you choose.
After preparing your terrarium and planting your selected plants, you will need to add some water. If this will be a closed container, this must be done carefully. It is easy to overwater, and once closed, the water will stay there. It's better to err on the side of too little water, than too much. You can always add more if needed, but the only way to remove excess water is to leave the cover off until it evaporates. Once the proper amount of water is added, close the container and relax. As the plants transpire water, it will recycle within the container. You may not need to add water for some time.
Assuming you started out with the proper amount of water, it could be six months or longer before you need to add water, depending on how well sealed your system is. Remember Dr. Ward from my column last month? It was four years for his fern and grass, without a drop of water added. Fertilizer should not be needed for a while, assuming you started out with a good soil mix.
If this sounds like the perfect winter project for you, give us a call. We have a guide sheet (G6520) which gives detailed instructions, as well as a list of plants suitable for terrariums and their environmental requirements.
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