Tam-Tam's Blog

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