When you’re setting out to build a terrarium, one of the most important things to check before you begin is that you have access to all the different terrarium-building supplies you need to make the project a success. Obviously, this is going to vary a great deal depending on the type of environment you want to create, but there are some things that every terrarium should have no matter what the end product will look like.
We’ve already devoted a page to talking about the various kinds of containers you can use to build your masterpiece, but we’ll stress again that its one of the most important choices you make, as the shape of container obviously defines the kinds of things you can put into it. Read more about terrarium containers here.
The next most important part of your terrarium supplies is the soil you use. What type of soil you choose to include is going to have to be determined by the type of plants you want to use and the type of environment you want to create. You won’t be able to create a very realistic cactus garden or other type of desert environment with peat moss, and moss and ferns will not grow well in loose, sandy desert soil. In most cases, however, you can get away with using ordinary potting soil that you purchase from any garden supply store. Unless you’re transplanting plants from out of doors into your terrarium (not recommended, but sometimes it’s necessary to get the right effect), don’t use soil from your garden or local green space. It’s not that it will be less effective for the plants, but it will be host to many different kinds of mold and mushroom spores, and potentially insects and insect larva which may hatch inside your terrarium and wreak havoc on it. Play it safe, and use the sterilized soil that you buy from a store. You can then adjust it to match your requirements by mixing in some sand, manure fertilizer, peat moss or sphagnum moss to create the right base for your plants.
Below the soil, the next layer of your terrarium should be a layer of pea gravel (basically just what the name implies – gravel that is made up of grains about the size of green garden peas). This might seem inconsequential, but it’s absolutely important to prevent your plants from getting drowned if you accidentally over-water it. Now, you might be saying to yourself, ‘well, I just won’t over-water it then!’ but mistakes happen, so include it.
Finally, the very bottom layer of your terrarium should be made up of crushed charcoal. Not crushed into a powder, but crushed into pieces smaller than the pea gravel that you use in order to stop them from sharing tasks with each other. This layer of charcoal is especially invaluable in closed-style terrariums, as it helps to filter and purify the water that is trapped in the container, preventing it from become stagnant and actively harmful to the plants it shares the terrarium with.
Bonus tip for the green community: If you already compost your organic food waste for your garden, you know how valuable it can be as a fertilizer. Try creating two layers of soil – one with some compost mixed in, and then on the very top layer, pure potting soil. This will allow the plants to finish decomposing the compost and gain additional vital nutrients. If you don’t already compost, consider saving some of the vegetable off-cuts from your next couple of days of food prep and placing them into terrarium in the same double-layering process mentioned above.
For those of you who are including compost in your terrarium, those of you who are creating closed-style terrariums and especially those you who do both, include an earthworm or two to help speed the composting process along and keep the noice nice and aerated. This will dramatically increase the lifespan of your terrarium. Since earthworms are hermaphroditic, if you include two of them and there is enough food for them, you’ll wind up with a perpetual cycle of earthworms beneath the soil, further adding to your terrarium ecosystem. (earthworms can also be purchased in bulk from some garden supply stores, and if you can’t find one near you that does, try looking for an outdoors store that sells live earthworms as fishing bait.
No terrarium supply list is complete without water. It might seem so obvious that it shouldn’t even be in this list, but as in any ecosystem based on Earth, water is the most important element in it. This is especially true in the miniature environment of a terrarium, where the smallest problem becomes magnified a thousand-fold and might even ruin your project. This is especially true when it comes to using tap water from any home in North America (this might also apply to many other places in the developed world, but I can’t say for sure). In North America, all tap water has been chlorinated to make 100% sure it is safe for humans to drink, but the plants inside your terrarium aren’t likely to adapted to handle the chlorine. In many places, the water has also been fluoridated and may contain even more unintentional additives and issues. Fortunately, there are several simple ways around this problem. First, and most expensively, you can simply water your terrarium with bottled distilled water. Distilled water has been evaporated and allowed to re-condense, leaving many of the more harmful substances behind. Alternatively, you can simply plan ahead in your watering schedule and fill a container with tap water a day or two ahead of time. Leave it out and uncovered in the open, and since the chlorine will evaporate faster than the water, you’ll be left with water that should be safe for plants of all types to use.
Supplies for Advanced Terrarium Builders
For those of you who are intent on building some truly beautiful and unique advanced terrariums, it’s also important to talk about plant foods, fertilizers, and the various types of PH and soil balancers that can be crucial to the success of more specialized environments. We talked briefly about the values of compost, but the full range of fertilizers deserves an entire page of its own, as does the various ways to manipulate soil composition. It might sound a bit dull to some of you, but they can make all the difference in the health of more exotic plant species.
With the proper terrarium supplies, any project can be a success. As in most things in life, you get out of it what you put into it – so put in the very best possible supplies, and you’ll get the best possible terrarium for years to come!