If you have ever purchased regular potting soil, you have may have noticed these little white rock like looking puffs of popcorn inside. These components in the soil mixture is called Perlite. It is there for a very important reason – to allow your plants roots to breathe!
What is Perlite?
Perlite is one of the more common growing substrates for those planning to start growing indoor plants and succulents. It is cheap and has many advantages over other growing media like coco coir, peat moss etc.
The main disadvantage is that it is not good at holding water. Watering more often becomes necessary when using perlite soil as compared to another medium. Perlite offers no nutritional or microbial benefit to plants or the soil as it not a fertilizer. But besides that, it has many advantages which you can’t ignore.
Perlite is not actually “soil” as it is a type of volcanic glass, and its main property is that it has lots of air pockets. It was initially used in the construction industry as an additive in concrete to make it lightweight, but obviously, plant growers found its other uses. Perlite is non-toxic and very lightweight
It it most commonly used as a soil additive but can also be used as a growing medium. Its benefits are derived solely from keeping the soil structure loose and light.
Why Use Perlite?
For those who don’t know much about Perlite, here are the reasons why it is very important in hydroponic/aeroponic systems for house plant cultivation:
- Grow roots can easily access oxygen present in the air pockets within the media. So roots stay thick and healthy always.
- Roots grow mostly horizontally in perlite substrate, allowing plants to grow more open and consume more light exposure. This helps leaves develop healthier and larger for greater photosynthesis.
- No need to worry about pH levels or nutrient lockout when using Perlite as a growing medium. It does not lock out nutrients, because it does not contain nutrients that can lockout. No pH level adjustment is needed.
- Perlite gives good drainage, and this helps to control the growth of dreaded fungus gnats, which are very common when growing plants indoors using any other soilless/coco coir grow mediums like peat moss, cocopeat, etc. So perlite soil is an excellent option for organic house plant cultivation.
- Perlite allows oxygen to freely flow between roots and the atmosphere, which helps in the rooting of new cuttings/clones.
- Those growing plants indoors using perlite soil can easily transplant them into any other medium later without many problems. If you plan to plant your house plants indoors using perlite soil as the growing medium, and if you want to grow them outdoors later too, then Perlite will be a great option as it is effortless to transplant.
- Perlite does not compact over time, so that means there is enough airspace for the roots to breathe.
- Perlite has excellent drainage properties, so it keeps plants from sitting in their own waste or overwatering, which can kill your plants. If you are using soil as a growing medium, make sure to be extra careful about overwatering and use top-quality hydroponic nutrients like General Hydroponics Flora Trio, which provides the right amount of nutrients directly to plants.
- Perlite can easily be mixed with other grow media like coco coir and peat moss. These ways, you have more control over your growing environment.
- Compared to other soilless/coco coir grow mediums perlite soil is a lot cheaper, and can easily be accessed.
- Perlite does not retain smell at all, so it’s good for odor control as well if you are growing inside where you you want to maintain fresh and clean air throughout.
- Perlite has been approved by NASA to be used on Space Shuttle to protect delicate equipment against extreme changes in air pressure and temperature.
What Size Perlite to Use?
So as you can see that Perlite is a very good medium for house plant cultivation, and it also has great benefits when used by indoor growers. It has been around for quite some time now, maybe decades or even longer than that, so there is no doubt that Perlite is an excellent quality medium to grow house plants and indoor vegetables using hydroponics/aeroponics too.
You can find Perlite at any local garden store in your area, or even online if they don’t have it where you live. If you are buying it online, make sure to choose one with a larger particle size like 2mm-5mm.
The reason why you want to get the larger particle size is because large air pockets are needed for roots to access oxygen and also make it easier for you when transplanting into other growing mediums later on without much problems.
What Types of Plants grow Best with Perlite?
Now that we know a little bit about Perlite and what it’s used for, let’s talk about how well some plants grow in such medium. You can use any small-medium sized plant material as long as you are using large particle size (2mm-5mm) perlite. Some examples of plants which grow best with Perlite include maranta, sansevieria (see picture below), dracaena, etc.
Every plant has it’s own unique form of preferences and Perlite is no different. Here are some plants which grow best with Perlite:
Some plants which grow well with Perlite include: Maranta, Sanseveria, Dracaena and ZZ Plants.
Maranta – One of the easiest house plants to grow.
They are pretty much indestructible, and they do really well in medium-light conditions. Maranta grows best when roots have good access to air (like with Perlite), so it can grow healthy green leaves that carry a lot of oxygen.
Sanseveria – Also know as the snake plant.
Extremely easy to grow in Perlite and can survive almost anywhere, even if you forget to water them for weeks. They don’t do too well when it’s too hot, so make sure your grow room is not too hot, like 85 degrees Fahrenheit or higher.
Dracaena – Dracaena is a pretty famous house plant due to its characteristic look, which resembles a tree.
It does well with Perlite, although it’s easier to grow if you have some soil remnants with organic material mixed in.
ZZ plant – This is another popular house plant known for its tolerance of extremely low light and low humidity conditions.
ZZ plants do well in Perlite, but you might want to give them some soil remnants like peat or coco coir mixed with Perlite too for faster growth.
Can you make your own Perlite?
If you want to save a little bit of money and don’t mind getting your hands dirty, or maybe if you are growing in a country where Perlite is not available, then it’s fairly easy to make your own. You will need:
- Clay (clay from the river bank works best) – You can also try using volcanic ash from a volcano.
- Sand (any kind of sand will do) – You can also try using clean playground sand or beach sand.
- Organic material like rice husks/ground coffee/roots/etc.
Fill your glass container with the right amount of clay and about 50% sand, then add organic material for perhaps another 10% sand. Keep adding organic material until the total volume of your mix is about 70-80%.
Once you have made the mixture, wet it and put it in a cardboard box which has holes in it so that excess water can drain out easily. Seeds can be planted directly into this homemade medium, or you can first transplant them into other growing mediums once the seedlings are big enough.
What are some other alternative to Perlite for growing plants?
If you don’t have access to perlite soil or if you can’t find it easily in your area then there is another awesome option too. It’s called volcanic rock dust, also known as “Vermiculite”. You can use vermiculite as a substitute for Perlite, or even mix them both together in equal parts.
Perlite For Succulents?
Succulents are a good example of plants that prefer soil for their growing medium. As such, Perlite can work well as an alternative to any other kind of soil too, especially if you want to grow some cactus or succulent plants indoors.
If you want your succulents to grow the best they can, then make sure to mix the Perlite with some good organic material (see above). This will give the succulent something to hold onto while it develops, and also gives it a way to get some nutrition from.
For example, a little bit of soil in a grow tent would work great as an alternative growing medium if you want to grow succulents with perlite soil.
You have got to get your hands on some perlite if you want to grow plants indoors.