Tam-Tam's Blog

Terrarium Maintenance
Jan 23, 2008 | 5:50 PM PST
Tags: terrarium , maintenance , pruning

The theory is, with the ideal conditions met, the average plant could survive in a terrarium for up to fifty years without attention.  This means you would have to have the ideal growing medium, the ideal amount of light, and a constant ideal temperature.  Chances are that any given terrarium may have one or more of these conditions that are out of sync with the "ideal" recommendation.  So if you decide to become a glass gardener, realize that varying degrees of maintenance will be involved. 

Moisture:
Possible signs of insufficient moisture:  no condensation on the walls of the container.  Plants are drooping.  The foliage is becoming brittle.  Dried up moss or parched-looking soil.

Possible signs of too much moisture:  Decaying foliage and plant rot.  Extremely heavy "rain clouds" on the container walls.  Remember, too much sunlight can cause excessive condensation to form.

If you have a tank style terrarium, you can check the moisture level by feeling the soil about one inch below the surface.  Although there is no real way to accurately check the moisture in narrow-neck containers, experienced glass gardeners say they can tell by the weight of the narrow-necked containers.  If the container seems light, they add water with a hand sprinkler or a long spouted watering can.

Light:
If you are using natural light for your glass garden, keep in mind that the amount of light the terrarium receives can change at any given time, especially with the seasons.  This means that vegetation can get too much sunlight at times and not enough at others.

If the leaves of the foliage turns yellow or look "burnt", this may be signs of too much sunlight. On the other hand, if the blossoms on flowering vegetation seem to retard, this may be a sign of insufficient light.

If the terrarium is exposed to too much light, it needs to be moved to a shadier spot, or sheltered from the direct light or the heat from the spotlights.  Sometimes the intensity of the sunlight is less in the wintertime months and the terrarium may need to be moved to a sunnier location or provided with the aid of artificial light.

Unless the terrarium plantings are receiving evenly distributed light from an overhead light source, the terrarium vegetation may experience tropism.  This means that the plants will twist and lean toward the light source.  If your cylindrical containers are experiencing tropism, you can turn the container a half turn.  For oblong (tank) containers you can turn them completely around.  When the plants straighten up, (may take a day or two) you can turn them back to their normal positions.

Pruning:
Keep in mind that you want the soil to have just enough nutrients for slow steady growth in the terrarium.  If the soil is too fertile it causes lush, rampant growth that takes over the design elements of the garden.  Extra growth can be kept in check by pruning the overgrown branches and excess foliage, or removing the plant once it has become too large for the container.  Make sure you know how each plant will need to be pruned because some plants can be killed by cutting the tops off, while others like spreading plants can be kept in check by removing unwanted growth.  Removing fading or spent blossoms, yellowing or dead leaves and stems, and side shoots helps to maintain the beauty of your glass garden.

When trimming plants in a wide mouth container you can use grabbers or tongs to hold the plant while using the pruning shears made from the wooden dowel with the razor blade, to cut away overgrowth and unsightly foliage.  Then use the grabbers or tongs to remove the pruned material.  Narrow-neck containers are usually to difficult to prune, thus it is usually easier to just reconstruct the entire planting.

Pruning Tips: 
Trailing plants like ivies can be pruned by simply shearing off unwanted growth. Strawberry begonias and other plants that send out runners can be pruned by cutting off the offshoots.
Cutting the tops off of coleus and impatiens can stimulate growth along the main stem.
Pruning a fern by slicing some of the outside fronds (leaves) below the soil line with a single edge razor blade will encourage additional new, low growth.  One of the best ways to trim a fern is to remove the plant from the container and separate it into smaller individual plants.  If you plan on trimming the outside fronds make sure to do it a little at a time, otherwise you may injure the plant.

Insects:
Your first thought may be that the plants in a terrarium will be protected from insects.  This is true, that is if there are no hitch-hikers.  Harmful pest can hide in the root ball of potted plants and live moss may be hiding eggs of harmful species, especially if the moss is collected from woodland areas.

Try spraying the plants with a houseplant insecticide before planting them in the terrarium, making sure to follow the directions.  It may seem neat to watch these little critters in the terrarium, but remember, these pests will strip down and destroy your glass garden in no time.  As soon as you see an insect in the terrarium, you should spray the plant(s) with a general-purpose insecticide.  Make sure to follow the directions for the insecticide you are using and be careful of over spraying the plants. 

Don't forget to remove all traces of the spray from the inside walls as soon as possible.  Depending on the size of the container, you may be able to place pieces of paper against the wall of the container to help with overspray.  The walls of a narrow-neck container may be cleaned off with a piece of lint free cloth wrapped around the end of a dowel and fastened with a rubber-band.

Make sure to leave the cover off the container after spraying, to allow the fumes to evaporate.  It may take several applications sprayed three or four times at weekly intervals to get rid of pest infestations such as whiteflies.

Mold:
The humidity in the terrarium provides an ideal environment for mold.  Mold is the most common disease that glass gardeners have to deal with.  The wooly looking growth that spreads over the soil is produced by a variety of gray fungus.  Although the mold may be due to an infected plant, the usual case is too much moisture.  Mold will develop very quickly and will destroy a planting in a very short time.

Hopefully, removing the infected plant will stop the growth of mold.  Make sure to properly destroy the infected plant and that it does not come in contact with the new plant that will replace it.  If needed, dust the garden with a general-purpose fungicide being sure to follow the directions.  If the dusting does not alleviate the situation, the terrarium must be dismantled and replanted.

There is no guarantee, but...
hopefully with regular maintenance your terrarium will function properly for a long time.  But as you can see, sometimes things go wrong.  Maybe the plants are growing to fast and need to be replaced, or there is some kind of problem that makes it necessary to just empty the container, wash it out and start all over.  Try not to let this get you down or frustrated. Like any other form of gardening, learning how to do it is part of the fun.  Good Luck!

Next up:  Other stuff you can do with a terrarium.

Terrariums-The Basics-Part Four:
Jan 10, 2008 | 2:54 PM PST
Tags: terrarium , planting techniques , tools , landscaping , soil , ideas

Planting Techniques:

Gather your materials:
Before you begin your terrarium project, gather all your materials.  Beginners usually make the mistake of planting right away.  Take time to make sure you have everything.  A good way to do this is to make a checklist. Some of the items on your checklist-- the container, the location the container will be when planted, the plants, tools, soil, gravel or any other items you will need.

Tools:
You can find tools designed for terrarium gardening, including small rakes and spades. You can also use children's toy gardening tools, iced-tea spoons, long handled forks, chopsticks, ice-picks, anything that can be used to make holes, move and arrange soil and lift plants. 

Different sized dowels are great tools for the glass gardener.  A dowel with a sharp pointed end is ideal for planting in bottles.  You can use dowels to dig holes, move rocks, even prop up plants.  Secure a cork on the end and you have a soil tamper.  Insert a razor blade in the end of a split dowel and secure it and you have a long handled pruner.

A long piece of coat hanger wire with an open loop at one end makes a handy plant hook that can be slipped around a plant to lower it into the container or into a prepared hole.  The plant is held in place with a dowel and the loop is released from the plant.  You could also use grabbers or tongs.  Don't forget to check out the tools used for planted aquariums, some will work well for the glass gardener.

Other tools to think about would be scissors, funnels, a mister, a watering can with a long spout and a kitchen bulb baster.  When watering bottles or containers with small openings, use the long spout of the watering can, to let the stream of water run down the sides of the container.  This cleans the side of the container as it breaks the force of the water stream.  A kitchen bulb baster really helps when you need a large amount of water in a specific area of the terrarium.

When collecting tools, think about the tools you use in the garden, now mentally shrink them down to a size to be use for terrariums and then think about how you can make your own.  It's part of the fun.

Soil:
Commercial potting mixes is the easy route to go at first.  You can match up the soil mix to the plant's needs.  These potting mixes will be free of the undesirable things like diseases and insects etc.  They also include sufficient nutrients to meet the demands of terrarium plantings.  As you gain experience you can create your own general purpose mix.

Use the container's height to determine how much soil should be placed in it.  The rule is: an inch of soil for each four inches of container height.  When applying this formula include the material used for drainage----one-eight of an inch of gravel for every inch of soil.  Thus five inches of soil required by a planter twenty inches tall incorporate 1 &1/8 inches of gravel.

Wide mouthed containers can be filled easily by pouring the soil in or using a trowel or large kitchen spoon.  You can use a funnel for the bottles or containers with small openings.  A piece of heavy paper rolled up into a cone can also be used.

Gravel:
Drainage material is a must for all terrariums.  Otherwise the soil becomes water soaked and the roots of plants will rot.  When the soil is saturated, it blocks out the oxygen that the roots need, it can lead to disease and have a bad odor. 

You can use crushed rock, pebbles, or even pieces of broken clay pots.  But aquarium gravel is best when working with containers with narrow openings.  Using a tube attached to a funnel makes it easier to spread the aquarium gravel in containers with small openings.  Just make sure the aquarium gravel is not wet, it will clog the funnel.

Moss:
A layer of moss soaks up moisture, which helps the lower section of the container from becoming mud stained, but this is not necessary.  You can use living or dried moss as a lining but the live moss is more attractive peeking along the edges of the container, living moss would be put in the container with the green "living" side down.  You can find moss in damp wooded areas or around half buried rocks and boulders.  You might be able to find a source online. 

Sphagnum moss comes dried and sterilized. It must be saturated by soaking it overnight, then squeezed damp dry, before placing it in the container.  Besides being a liner, moss is very helpful as a layer between the drainage material and the soil, it will keep the soil from sifting down through the drainage material.  Sphagnum moss is the best choice for this layer.

Plant Placement:
Once the container has been chosen, and the plants have been selected, and all the tools and materials gathered, you can work on plant placement. 

If the selected plants are in individual pots and the pots can be easily set inside the container, you can simply move the plants around until the arrangement suits you.  If the container has a smaller opening or a narrow neck, you can move the plants around on the table to get a general idea of how to place them.  If the plants are not in individual pots, sketching a few garden designs to help you decide how to plant your garden would be better than removing the plants from the container and moving them around, losing the soil around the roots, and possibly damaging the root system as well.

First decide on a focal plant.  This plant will be the focal plant for the terrarium, and since it will be centrally located in the container and will tie the garden together, it should have very colorful or interesting foliage or blooms.

After setting the focal plant in place, arrange the other plants around it to create a desired effect.  You may want to try keeping all the vegetation in proportion to a container's size.  Don't forget that you may have to prune some of the plants and you will need to leave some gaps in between them to let them grow.  If the gaps feel to big in size you can temporarily fill them with moss, pebbles, or bits of redwood bark. 

Remember that the tallest plant usually is planted first, in the back, and the focal plant and the others are then planted.  A basic design is tall plants in the background.  Mid-size plants and/or focal plant in the middle.  Then accent plants along the sides with smaller plants in the foreground.  Keep in mind that a more complicated landscape design might be easier to plant outward from the center.

Landscaping:
Driftwood, bark, pebbles, or stones can be used as the focal point instead of a plant in landscaped terrariums.  Be very careful about what stones you use.  Heavy stones can break the bottom out of your glass terrarium.  Featherock is a great substitute for making "boulders" or ledges.  Sold at gardening and landscaping centers, Featherock is a lightweight volcanic rock that can be broken into chunks, it splits easily, and can be hollowed out quite easily with a hammer and chisel. 

I've used Featherock in my aquariums before and while it is easy to work with, it is also dangerous.  Featherock breaks off into tiny shards of glass like splinters. Always wear work gloves, eye protection and a mask when working with this natural material.  You can carve out a nice crater and add soil and plant a little plant in it and make a very attractive accents for your terrarium.  Featherock is also used in water fountains and other features in the garden.

Also, don't overlook the manmade objects.  Of course you have to make sure it can withstand the heat and humidity of the terrarium.  Using a mirror or part of one can give the illusion that the landscape has a lake or stream.  Any small container that can hold water will be even better.  A rectangle container can be used and small pebbles can be placed along it to give the look of an irregular shoreline.

Use your imagination but keep your design realistic.  That doesn't mean your landscape can't be whimsical or based on fantasy, just make sure that all the little do-dads and figurines don't overpower the final design.  These touches should accent the landscape and make it feel magical, if this is the design you are going for.  If you think about it, you wouldn't find a little lamb in a tropical forest, so why put a little ceramic lamb in the terrarium with tropical plants, or a figurine of a fisherman in a desert terrarium?  You can also just keep the design of the landscape all natural, using natural materials.  The possibilities are endless, as they say.

Basic Tool Checklist:
rake
spade
scissors
long spouted watering can; mister
long handled fork
long handled spoon
chopstick; kitchen bulb baster
ice-pick (remember to keep point covered when not in use.)
dowels
cork fastened to a dowel to tamp soil
razor blade secured into a split dowel for prunning
coat hanger wire hooked on one end to help with the plants
grabbers (like tongs)
funnels (might need some clear tubing to attach to the funnel for bottles)

Next: The Tank Terrarium- step by step

    

    

Terrariums...figuring out how it works.
Dec 12, 2007 | 8:28 PM PST
Tags: Terrarium , Photosynthesis , Respiration , Rain cycle

If you think about the processes that take place during a plant's life, you can get an idea as to why this little glass case would work so well.  The processes of Photosynthesis and Respiration, the refresher course: 
Photosynthesis goes on in the presence of light, sunlight or the use of special growing lights for plants.  It occurs in the green cells only and uses carbon dioxide and water, releases oxygen and the plants increase in weight and store food. 
Respiration goes on all the time, in the light and in the dark, it occurs in every living cell of the plant, uses food and oxygen, releases water and carbon dioxide, and the plant decreases in weight.   These two processes are interdependent, they happen at the same time.  The material created by one process makes the other process possible.  So these two processes is how the plant uses the energy of the sun to make their own food called plant sugars---from carbon dioxide in the air and from water in the soil.  Some of these sugars are used as soon as they are made, while other amounts of the plant sugars are store in the leaves and stems and they are converted to food as the plant grows.  

So how does the terrarium work?  Basically it encapsulates the proper growing conditions.  For instance, the high humidity that numerous plants need is maintained constantly in the sealed terrarium.  It blocks off drafts and protects from excessive heat or cold, if positioned properly.  The "sunlight" provided by the lighting system can be optimal for the process of photosynthesis.  One key factor is moisture.  Moisture has to be introduced into the terrarium, because it is a self contained unit.  Once this has occurred, the process of photosynthesis can begin but this also produces the process of the rain cycle.  

In the rain cycle, the water that is absorbed by the plants roots are released as vapor through the leaves, the vapor evaporates into the air and eventually falls back into the dirt through the process of condensation.  As the moist vapors rising form the plants reaches the cooler glass, it condenses, dripping to the dirt like raindrops from the glass.  Because the water is again absorbed through the roots, this becomes a never-ending process.
Once the rain cycle has been established, the terrarium garden has a constant supply of moisture.  This means that the terrarium never has to be watered as long as condensation "fogs" the sides of the container.  The tight fitting lid or cover allows this rain cycle to happen constantly, but it also keeps the gases needed for photosynthesis and respiration from escaping.   

When thinking about terrariums two types come to mind--Tropical and Desert.  Several tropical plants prefer humidity, this makes it hard to keep these plants healthy in the dry heat we use for the winter.  This can make the terrarium a great idea for slow or low growing tropical plants.  On the other hand, desert plants like the dry air and the terrarium can make an ideal place for them to thrive.  Desert terrariums do not need the completely sealed covers.  In fact they need to have a supply of dry air to benefit their growing conditions.  Cacti and succulents make for a very interesting garden design.  When you set up a terrarium for animals, such as some type of small lizard, it becomes a Vivarium.

Next...the basics.  It's more simple than you might think.