Growing medium, compost and soil
Plants are normally grown in a nutrient that contains “growing media“or”growing medium“Which can be compost or soil, although it is often one peat or peat-free mix.
You can normally use these products directly from the bag and get fantastic results, so why write a comprehensive article on the subject? Many indoor gardeners like to have some control over the “blends” they use, especially since not all houseplants like the same thing.
Others like to create their own “blends” from the beginning so you want to learn more about what they can use or you might just want to address the difference between Perlite and vermiculite. Either way, yours houseplants will only be as healthy as their roots so it is important to understand and encourage good root health and this starts with understanding the materials that surround and support them.
What make a good indoor pot mix?
Most houseplants will often be pleasantly happy in several different growing medium types, so there is usually not a magical type for each plant.
As a general rule, all houseplants need a growing medium that is sufficient “Open“and”solve“enough to allow its roots to grow through fairly easily, but not so open that the plant cannot remain rooted in the pot.
As a general rule, all houseplants need one growing medium that’s enough “Open“and”solve“enough to grow its roots
It must be open and loose so that water can flow through the soil but not so open that water literally just flows out of the bottom otherwise your plant has nothing to drink. It also cannot be too “closed”, otherwise the plant becomes waterproof which causes the roots to rot.
If a growing medium can hold water and allow air in it, then it can support microorganisms and also hold nutrients which is crucial for plant health and growth. A good indoor mix allows the above to happen.
What is the best pot plant variety for houseplants?
Generally, most people will use 100% Peat, Peat free or Homemade compost for their houseplants. However, there are other frequently used materials that can also be added to make the perfect pot mix.
The use of Peat has become increasingly controversial in many countries in recent years. It is a truly exceptional growing medium for almost all houseplants, provides perfect moisture and nutrient retention and is quite slow to break down. It is cheap and easily accessible in most supermarkets and garden centers. It is also the most likely soil mixture to be found in the pots of your newly planted plants.
Peat is a completely rounder and generally excellent for all houseplants. So what’s the problem?
The question is that Peat comes from naturally occurring peatlands which are the most effective carbon sinks in the world. The harvesting of these peat areas destroys the surrounding environment and allows more CO 2 to exist in the atmosphere and in the long term affect climate change. It takes too long to form to be classified as truly renewable, so in principle it is not sustainable because we cannot realistically replace what we use.
But we still have to consider it Peat is a fantastic growing medium and will facilitate our growth, which in turn results in photosynthesis and creates a better natural cycle than those who burn peat as an energy source.
It’s obviously still not brilliant, which is why our personal view is that it’s a better idea to use Torvfri, or at least peat is reduced products where possible.
The rest of this article contains growing media that can be added to 100% peat products to “dilute” and get the peat moving on. So rather than just being able to repot 10 potted plants with a bag of peat, if you mix it with other effective ingredients you might be able to repot 20 potted plants and still get equally good results.
How to use it
Usually Peat can be used directly from the bag without any extra need. It often comes with already added nutrients and can feed a slowly growing potted plant for several months up to a year (depending on how fast it grows). If you have read the previous section, you will know that we will recommend adding other materials to get your turf purchase moving on.
Peat free pot composts will contain mixtures of organic materials such as coconut, green compost, shredded bark and then mixed with inorganic materials such as sharp sand and rockwool. This mixture of coarse and fine particles is needed to form a compost that can hold water and nutrients but also allows air into the mixture. All this is important for root growth.
Peat free Products are becoming increasingly popular, but as it is a fairly new market, there is not a main competitor or perfect “product”. This means that some perform better than others and that there are lots of different materials that may be in yours Peat free bag. If you can, get access to what’s inside the bag and have a feeling that for indoor plants you are looking for something that should be quite nice and smell quite comfortable.
How to use it
If you have chosen an unknown Peat free compost you may want to experiment a bit to check its suitability. Some blends can be very bulky and have large components that make them harder to work with and less useful for houseplants that may have small roots and pots. But all that is good, just like a 100% peat mix, you should be able to use this straight out of the bag.
Combine it with other growing media if desired, otherwise you should be pretty good to go as soon as you open the packaging.
You should not use Peat free products with carnivorous houseplants like Venus FlyTrap because they originate from peat ants and therefore best grow in Peat.
Homemade compost is very easy to do, great for the environment and often free (or at low cost).
You need a composter to get you started and a space in your garden to put it. It must also sit on soil so that worms and other beneficial organisms can actually access the material inside. Then just add green and brown waste and turn around “ingredients“every so often. After several months, your waste has turned into a compost that is a nectar of nutritious humus.
How to use it
Well rotten homemade compost can often be used to replace a bag with 100% peat, and can be used in the same way a peat-free mix you buy from a store (sometimes compost is what you actually buy when it’s labeled “peat-free“still!).
You have to be safe with it homemade compost that it is completely disintegrated and has not taken up too much of the surrounding earth’s nature. If your compost is on top of clay soil, for example, the resulting compost will have elements of clay, great for outdoor plants but maybe too heavy for indoors.
Many people say they use “dirt“scooped up from the garden or garden for their indoor plants. In some cases, this is wonderful stuff, but often when someone says”dirt“they talk about things that sit on the surface of their earth. Exposed and weathered for the elements actually makes it very poor quality, lacks nutrients and all the real ability to hold water.
TRUE topsoil sits just below this surface level and can be 8 inches / 20 cm deep and in ideal situations it is the perfect growing area for roots of outdoor plants. It has the highest concentration of organic matter and microorganisms and is where most of the soil’s biological activity occurs. This is the business.
How to use it
Topsoil while bursting with life and nutrients is not suitable as a single ingredient in your growing medium for indoor plants. It is not only expensive, it is incredibly heavy compared to peat or peat-free products that make it very difficult for plants in containers when their roots struggle to grow through it.
Topsoil is heavy because its components are very small and thus compact light, which means that there is no air for roots to breathe, it also means that it holds water well, but in itself too good. So to take advantage of the amazing features of topsoil you should mix it with other materials to keep it “Open“It is common to combine it with peat or peat-free products, the total amount topsoil in an indoor pot mix should usually be between 0% – 30%.
Well rotten HORSE or farm manure is a great way to enhance or add to a chosen growing medium. It holds water well and adds a large number of different nutrients. In most cases, a pot that only contains manure is too rich for almost all houseplants, the only exceptions are very heavy feeders like the banana. So it is much better to mix it with some other growing media mentioned in this article.
No matter how much you choose to use, it is important that you use well rotten manure – the fresh stuff is completely blown away by biological activity that basically burns itself out. The heat and the strong biological activity will damage or even destroy roots. In addition, it stinks.
So how do you know if it’s “well-rounded”? It is easy to answer, what you are looking for or rather smells like is a light earthy and maybe sweet scent. It should not smell foul or feel like mushrooms. Basically, if you are not comfortable holding it in bare hands – it is not ready.
How to use it
You should not use manure in excessive amount when it comes to houseplants because it is often too rich and holds water too well, which in turn will encourage over-watering and rot.
A mixture that contains 40% at most, and even then only for gross feeders, such as The Swiss Cheese Plant. You can use a small amount of fertilizer in the houseplant mix (10%) for most houseplants except those that thrive in nutrient-poor soil such as Venus Fly Trap and most cacti.
Sphagnum peat / peat moss
Sphagnum Often called peat Moss and although it is linked to dried “peat” it does not have the associated controversy because it is quite renewable and Sphagnum is often used in its living form. It may be best for the novice indoor gardener to miss it as Sphagnum is Alive and thus need care itself to survive and continue to support potted grows in it.
How to use it
Both living and dead cells from Sphagnum Moss can hold large amounts of water in their cells – up to 25 times as much water as their dry weight! This makes it a fantastic soilless material for some houseplants. You can’t “mix” it with peat or compost if you want to keep it alive, but you can sit on the upper surface of the growing medium to create an attractive look and help keep water.
It is usually used to grow houseplants that have large thick roots that are preferably exposed to light like those from Moth Orchid, although you can also find it that supports various succulents such as House Leek.
White Perlite remains white. No matter how long it stays in the muck, it keeps its bright appearance, which can add some decorative appeal to your soil mixes. But it also has a much more practical application.
In its natural form it is quite dense almost like a small stone, but when heated it expands and although at first glance you may think it is heavy it is really light. The closest way to describe it is to think Polystyrene / Styrofoam (which is actually quite awful, but it’s a different story) perlite, although a non-renewable resource is still very plentiful and when it comes to gardening, only small amounts are ever used.
How to use it
Perlite is a lightweight product that holds a little water and keeps growing medium “open”. In general, you only use small amounts in a soil mixture because too much causes it to be very free drainage and nutrients poor. Of course, this type of effect has its place, perhaps for young plants or cuttings in house plants where too much moisture saturation would cause rot.
You can also use Vermiculite (see below) as a similar product vermiculite as a general rule will hold more water.
vermiculite used in many different ways, from house insulation to fire protection, and as you would expect, it can also be used by gardeners indoors. However, there is some free drainage vermiculite also several times holds its own weight in water, which makes it ideal in pot mixes. Just like Perlite, it is very light and reasonably cheap, although you should always use fresh rather than trying to use the old stuff from the wind!
How to use it
vermiculite is very similar Perlite in that it will help keep your growing media “open”, it is more discreet than the rival’s bright white appearance, but it tends to hold more water because of its mushroom-like absorbent nature.
If you have the choice, use vermiculite over Perlite when you have houseplants that need a lot of watering. You can use 100% vermiculite (or perlite) for cuttings but it is normal to reduce this drastically when the plant is up and growing (0% – 20%) as it does not hold nutrients well and without them your plant will suffer.
Gravel and grit
Gravel and Gravel available in many colors, shapes and sizes, although you must make sure you use garden gravel or Gravel. Everything else will not be designed to mix the pot and can be contaminated with chemicals or simply have too large pieces.
Prices may vary widely but usually you will not spend much so little will go a long way.
How to use it
Unlike vermiculite and Perlite, Gravel and Gravel holds no water at all, although it will still keep your houseplant mix “open” and free drainage. It can also place weight on containers for top-heavy plants to prevent them from tipping over. Applying a layer to the surface also helps retain water and prevents the rest of your growing medium from drying out so quickly.
A composition with a reasonable amount of grain is perfect for houseplants that do not like watering, like cacti, but for typical houseplants it should only be a small amount of the actual mixture, preferably less than 5%.
If your primary purpose in using it is to add weight, you may want to consider adding a layer at the bottom of the pot or on the ground surface rather than where roots will grow.
Sharp Sand / Coir
There are plenty of other organic and inorganic materials that can be added to pot water mixtures to improve drainage or improve the consistency of the final result. If people keep moving away peat based products, the options are likely to increase over time. Sharp sand and Coconut Coir are two fairly common substances currently in use, both of which can already be found in the peat-free products sold in your local stores, but you can of course actively add these to your own blends.
How to use it
Sharp sand improves drainage because the small grains cannot hold water and they prevent the other material from clumping and compressing. Like Topsoil, however, these are heavy things and are not a good material to have in a large amount, even the cactus would struggle to thrive in a high concentration of Sharp sand.
Coconut Coir is a natural fiber extracted from the shell of coconut which has excellent water retention properties while retaining structure and allowing air to circulate. It comes in two shapes, roughly shredded or fine.
The shredded version is good to combine with Peat, also compost etc., where the fine version can sometimes be used as a complete Peat free alternative in itself. Of course, you can combine it with many other materials, including those discussed above.