Terrarium substrates are the well-balanced diet that forms the foundation of your system.
There to maintain form and function and provide nutrients and hydration, they are an (inevitably messy, but) essential part of the entire terrarium process.
Ultimately, what you choose to plant will determine how well your plants will be able to grow and nourish themselves.
And each plant has different needs…
Get it wrong and you risk stunted plants, rot, insect infestations, and more. Therefore, it is always worth taking the time to consider the best substrate.mix.
Oh, you thought it was a done deal? Sorry,a mixture is always the best option– then brace yourself for a comprehensive guide on preparing the ideal mix for your next project (along with deep dives on each individual element).
Let's go digging!
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- The main components of a substrate mixture.
- Recommended bases for terrarium soil/substrate
- Terrarium soils not recommended (or at least not ideal)
- Useful soil/substrate supplements for terrariums
- Substrate mixtures for terrariums of confidence
- Frequently asked questions about the terrarium substrate
- now for you
The main components of a substrate mixture.
Like a good cocktail recipe, each ingredient is designed to balance and complement each other.
A certain tart sweetness, shall we say?
Daisies, I'm looking at you...
The same is true for a terrarium substrate mix. Do you want to achieve the ideal balance ofWater retention,sewer system,support,mifortaleza.
Which can be a bit daunting at first, but that's why we have a recipe!
Starting with a proper base, you add different amounts of soil supplements based on the needs of your plants and the environment.
- Base– Base makes up the core of your mix (about half overall) and provides support and water retention.
- structured elements– These materials provide some much-needed resourcesDrainage and root aeration for your plants.
- Moisture Retention Materials – If necessary, supplement with additional water retention materials, depending on how the plants you choose like water.
- Compound– If you are using completely inorganic components (or if you want to give your plants a head start), you will need to supplement with some organic material.
Fear not, whether you're an experienced mixologist or new to the game, everything will be clear.
The rest of this article describesall our recommended materialsfor each part of the recipe and how to decide which one is right for you.
Recommended bases for terrarium soil/substrate
Coco (pronounced [Kwoy-uh]... Apparently)
coconut fiberis a fibrous material made from coconut shell, and ismy favorite substrate basework with.
It comes in a variety of forms; from a single dry brick (which needs to be rehydrated) to bags of coarse chips and finely ground powders, the latter of which is the best in my experience.
The larger chips/fibers certainly provide better drainage, but the powder is a dream to plant. It's super light and fluffy, which means you'll get plenty of root aeration and tons of moisture retention.miit will not compress over time. What could not be loved?
Well, coconut fiber is just as popular as the base for yourstabilitymireliability.
Being a refined material, it will not spoil in your terrarium (at least not for a while).verya long time), it is not susceptible to pests and can beeasier humidity control and drainageversus using random land bases.
Convinced?Check not Etsy.
The only caveat is that it does not contain any nutrients. Therefore, to properly support your plants, you will need to add a fertilizing element to your substrate (but more on that later in this article).
- High water retention
- Neutral pH and resistant to decomposition
- Natural, (more) sustainable product.
- pest resistant
- Does not contain nutrients
sphagnum mossit has become a true staple in the terrarium and vivarium industry (both live and canned, but canned is better for substrates).
Like coir, this wonderful material is fantastic for terrariums due to its excellent water retention and fluffy texture. Although perhaps just as important are the antimicrobial properties of Sphagnum moss, which help toreduce bacterial growthand thereforedecrease the rate of decomposition.
a valuable feature in a terrarium environment!
It is often used alone as a growth medium, sometimes as a substrate barrier, and often as an addition to mixes. Sphagnum moss is so versatile that it is unquestionably a staple material.mia potential supplement depending on how you use it.
You can buy bags of preserved sphagnum moss at a variety of stores.not Etsy here.
- High water retention
- acidic pH and really slows down decomposition
- readily available
- pest resistant
- It does not contain nutrients, therefore it should not be used alone.
- Opossiblyrest (but we are talking about a long time).
- Many sources are unsustainable.
Aquarium soil is regular soil that has been boiled to produce dry pellets.
It is an interesting option because it has all themineralsmipositive aspects of growthcommon potting soil, but commuch better drainage.
This is because the pellets are round, so they don't stick together in a uniform shape. They are also very strong, so they will withstand compaction for years.
Aquarium soil has become much more popular recently and is probably the only substrate that can be used on its own. While I find it difficult to plant on its own, I still think it's better as a base than a complete solution.
Grab a bag on Amazonwell hereand try it yourself.
- It is stable and does not compact for years.
- Excellent drainage and water retention.
- A great option for amalaria.
- The aesthetic of many blackheads may not be suitable for everyone.
- The soil granules are so hard that I thinka little hard to plant at times. You can't just press down on a plant's roots like you would a soft substrate.
Terrarium soils not recommended (or at least not ideal)
Only for glasses / mixture for glasses
Regular packaged potting soil is a universally available option.
It's affordable and will work for some plants, but it's not ideal for terrarium longevity.
The real weakness of potting soil is itsbad drainageand tendency tocompacttoo much. We all know what happens to wet earth, it turns into thick mud...
Growing conditions are not ideal for any plant, and manytropical terrarium plantshe just won't stand for it.
It is worth noting that “packagingmix” can mean a variety of things. You'll probably include some of the other things on this list (which isn't necessarily a bad thing), but it's important that you know what you're getting.
- It is affordable and readily available.
- It comes full of nutrients for your plants.
- It's sterilized, so you can be sure you're not adding bacteria or crawling insects to your mix that could pose a risk to your terrarium.
- Cigar for glasses onlyIn factit doesn't drain well, so your terrarium is at greater risk of rot.
- Not good for tropical plants that don't like soggy soil.
If you're making a native terrarium (meaning using local ingredients), soil taken from the local area is an option.
Without knowing its composition, it is a bit risky. Native terrariums bring many unknown factors and the soil may have things like rot, disease, or pests. But if the plants thrive outdoors, in theory they should thrive in a similar indoor environment.
SerpaDesign madea great videoon sourcing native terrarium building materials, if you're interested in going down that road.
Useful soil/substrate supplements for terrariums
Now, we come to the list of ingredients that build on your foundation and balance out the overall mix.
Many of these materials serve similar purposes, but they all have slightly different advantages and disadvantages. Therefore, it pays to understand your options before making a final selection.
perliteit is a type of white volcanic glass, which looks like styrofoam balls. That isluz,porous,and has a variety of uses in tropical terrariums.
Its unique structure allows it to retain water on its outer surface, without absorbing it internally, making it an excellent solution for providing constant water to plants without creating a soggy mix.
The granular structure of the material also helps to aerate a growing medium mix.
A little pearlite goes a long waysee here on Etsy.
- Perlite will not rot, degrade or break down, making it a reliable long-term addition to soil.
- Because it's so porous, perlite is great for aerating the soil and providing better drainage (perfect for tropical plants).
- White styrofoam balls don't look particularly natural in a terrarium. I don't like the way they look at all.
- Because they are so lightweight, I have heard of them "floating" to the top of a growing medium. I doubt you'll wake up one day to find them all over your plants, but it's something to keep in mind.
vermiculiteIt is very similar to perlite in function, but has a different appearance and structure. It is actually a mineral (aluminum-iron-magnesium silicate) and looks like flaky brown rocks.
It's truebetter at retaining water than perliteand can be a great addition to substrates forparticularlytropical plants hungry for moisture.
Check out Etsyto find a variety of vermiculite grades (particle sizes) that should be great for terrariums and other smaller pots.
- Unlike perlite, vermiculite actually holds and provides nutrients for growth.
- It looks more natural than perlite (IMHO).
- It provides the highest possible water retention of terrarium soil additives, making it the best solution for water-loving plants.
- It does not provide as much aeration/drainage as perlite.
Pumice is another type of volcanic glass that is more gravelly than its foamy white counterpart.
Often used in the bonsai industry, pumice has alightweight honeycomb structureand an open porous exterior, making it an excellent soil aerator and moisture retainer.
A wonderful little stone with a lot of versatility, I would choose this one if you are looking for a more natural looking perlite.
Etsy has a wide range of grades/sizes of pumice, but I recommend a finer grade.see them here.
- Ideal for aeration and water retention.
- good drainage.
- Natural look.
- It lasts indefinitely.
- None to speak.
orchid barkit is a more natural way to add granularity and aeration to a soil mix. It's a robust mix of bark chips (so called because it's often used for orchids, not from them) that helpsprovide structure and spacesin the middle floor
Finding a small enough mix for terrariums is the tricky part, it's usually very bulky.
Explore the variety of sizes and mixes of orchid barknot Etsy here.
- All natural and sustainable material.
- It actually looks natural!
- Ideal for root/soil aeration.
- It does not hold water as well as perlite or vermiculite.
- More susceptible to rot as it is a natural product.
If you are working with pure coco as a soil base, you will need to add some nutrients to your growing medium. Be careful when adding any homemade compost that may contain any rotted material, I would definitely go for something boxed whenever possible.
Fused worms are a great, readily available solution.
A nice way to say "worm poop",worm humusare compounds produced through the feeding actions of earthworms.
It is an all-natural fertilizer that also drains well and has a high water-holding capacity.
- ecologically correct.
- Slow release nutrients vs. liquid fertilizer.
- It has drainage and moisture retention properties.
Charcoal has been a horticulture staple for a long time, but its use in terrariums is much more varied.
Thanks to its highly absorbent nature, it can bind to contaminants in the terrarium, making it an often praised "cleaning" material. Although the effectiveness of this actionnot easy to quantify, charcoal still brings other positive qualities to a substrate mix.
It is capable of retaining moisture thanks to its porosity, and is often described as being able to store and deliver nutrients to plant roots.
It comes in a variety of forms, butcoaland activated charcoal are probably your best bets.
A fine powder is easier to distribute as part of a substrate mix, or go for a coarse option if used as a dedicated coating.
See activated charcoal on Etsy.
Sand can be an easy addition to your growing medium to increase its aeration and drainage. Coarser horticultural sand will work best, but any sand will do (with the exception of beach sand).
Obviously if you go to a desert terrarium you will have a much higher proportion of sand. Same goes for any cactus or succulent mix (check out mysucculent terrarium guidefor more information).
Personally, I prefer to useblack sandwhenever possible. That's how it isless visible in the substrateand the darker substrate contrasts better with green plants.
Substrate mixtures for terrariums of confidence
I get it, getting a custom substrate mix can be tricky and sometimes you may just want to run with a tried and true mix.
This section describes some of the most popular mixes, or you can also view ourEssential Guide to Tropical Terrariumswhere we make it easy for you by dividing our exclusive combination in a ratio format.
Named for its original development by the Atlanta Botanical Garden (not an abbreviation for its ingredients, as you might think)ABG mixis virtually the gold standard substrate fornurseries.
It is a precise mix oftree fern fiber, peat, coconut fiber, charcoal and orchid bark. Although the proportions seem to vary depending on where you look at the recipe.
The combination of materials provides excellent water retention and drainage, making it an excellent choice for tropical plants of all varieties. If the above DIY recipe doesn't work for you, this is the classic cocktail that's hard to mess up.
If you are looking for a soil mix but are afraid of making a mistake, the ABG mix might be a good starting point for you.
Frequently asked questions about the terrarium substrate
Would you recommend buying a terrarium soil kit?
If you're only planning to build a single terrarium, sure. Getting the exact amount right will reduce waste and simplify construction. However, they are expensive for what you get and it is not always possible to identify the source of each material or judge its quality.
What is the best terrarium soil recipe?
There is no single recipe for terrarium soil, it will depend on your plants and other terrarium conditions.
What is the bioactive substrate for terrariums?
bioactive terrarium substrateIt is designed to promote the growth of beneficial bacteria and fungi that help maintain the natural cycles of decomposition and other biological processes.
now for you
What is your favorite terrarium soil mix?
I would love to hear some specific examples of the mixes you use for different plants. After all, the more we know, the better we can take care of our plants.
Share them in the comments below.