Following is a nice handout prepared by Melissa Madigan for our upcoming Terrarium class (class to be held this Saturday in Brunswick, Cumberland and Falmouth. We still have openings in Brunswick at 10 AM--call them at 442-8111 or 1-800-339-8111 to reserve a spot!).
Making terrariums can be quick, easy and doesn't have to be expensive. To save money on your terrariums, shop discount stores, flea markets or consignment shops, where you can find really cheap yet great looking glass containers, jars or even goldfish bowls. The terrarium plants you’ll use are generally small houseplants, which often only cost a couple of bucks each. If you choose a really dramatic container and an attractive set of plants you can make a beautiful terrarium in less than an hour! Terrariums also make wonderful and impressive gifts, even for people who consider themselves plant-challenged.
There are three kinds of terrariums: Closed
Within the closed and open types there can either woodland or houseplant types, and all terrariums are governed by light.
Containers: they should be interesting and unique as possible, be made of clear glass and have an opening that you can easily work thru.
Drainage materials: mixed charcoal with rocks, sea glass or sand (or any other clean course material) this allows for good drainage of water in the terrarium
Spaghnum moss - this prevents the soil in your terrarium from settling down into the pebble layer. If you don’t like spaghnum moss you can use a piece of landscape fabric.
Then top that all off with good organic soil.
Plants: there are lots of great terrarium plants to choose from. Make sure to buy plants that are small enough to fit into your terrarium jar. Select an odd number of plants with a variety of leaf shapes, color and textures. Some good choices: Croton, Pothos, Dracaena, Small Ferns, Lucky Bamboo, Prayer Plant, Club moss, Creeping fig, Irish moss, Artillery fern, Polka dot plant, Aluminum plant, Peperomia, Ivy.
Watering: You should use either distilled water, or water that you have allowed to set out over night (this will help eliminate salt build up). Most terrariums will only need a light monthly watering. The thirst of plants in a terrarium (and in general) will vary according to the type of terrarium you have, the weather outside, the amount of light you are providing it, the type of heat in your home and room temperature. You can use a spray bottle or watering can with a rose attachment on the spout to water your terrarium. You don’t want it to be soaking wet, just damp. Err on the side of too little rather than too much water.
Right after you plant your terrarium you will need to balance the moisture content. You will do this by leaving the cover on for a few days and checking the condensation inside. If you have droplets formed at the top of your container or on the sides just above the moss, your moisture is correct. If you have overwatered and the entire terrarium is covered with heavy condensation, you should take the cover off, wipe out all the condensation and return the cover. You will keep doing this until you have just a few drops forming.
You can also use the spray bottle to clean off any dirt that has clung to the glass sides of your container, which you can then wipe clean with paper towel or newsprint.
Never use glass cleaner on the inside of a planted terrarium, as it could make your plants sick.
Light: Light is the food of plants. Without a good source of light, plants will gradually perish. However, do not move your plants around to follow the sun. Plants are oriented to the light an do not thrive if they have to repeatedly re-orient themselves. Do turn the terrarium gradually, over a period of time, if the plants are all growing to one side.Most flowering plants need sunlight to bloom. If you are unable to provide a good 4 to 6 hours of light try daylight in combination of fluorescent light or a grow light. Keep the lights on for at least 12 hours a day. Plants like regularity, so be consistent with the time you turn them on and off.Ongoing care: Water only when the soil feels dry to the touch, fertilize sparingly. You will want to replace plants that droop or develop spindly stems. Maintain the correct moisture and light levels to avoid problems. Remove spent blossoms on flowering plants and any leaves that drop off.