It is easy to grow plants in perlite or in perlite mixed soil. Perlite soil is the best growing medium for new growers. If you want to grow plants with fewer efforts then you should use it for growing plants.
You can mix it in container potting soil and add it as a soil amendment in your raised bed garden soil.
But do you know how to use perlite in your garden, what it is and pros and cons, etc?
In this perlite guide, you will learn everything about this easy to use a growing medium.
What is perlite or perlite soil?
It is a non-crystalline solid volcanic glass that is derived from the cooled magma. Natural perlite has a dark black or grey color but after the heat treatment, it gets its brilliant white color. When you look closely at perlite you will see tiny pores in it. These pores make it better than other lightweight growing mediums.
Because perlite store nutrients in these pores and drain out the excess water. Moreover, tiny pores increase air circulation and reduce the chances of root fungus.
The good news is it is a disease-free, toxin-free, clean material that is good for growing vegetables, herbs, and houseplants.
Perlite is a famous industrial mineral. It is used in ceiling tiles, roof plasters, masonry due to its lightweight. Nowadays it is the most widely used as the soil amendment in horticulture.
How they make perlite?
Perlite glass is a solid material that contains a high percentage of water. It needs to be treated in the industries to make it ready for our use. The manufacturers of perlite buy volcanic glass in tonnes. Then they crush the glass to make tiny pieces of it. These small pieces are further sent to the industrial oven section for the heat treatment.
Where they put them in the industrial ovens at the temperature of 900 degrees C. Due to high heat the water content evaporates quickly. The tiny solid pieces of volcanic glass popup like popcorn and we get ready to use white color perlite.
Volcanic glass has the ability to expand up to 15 times its size after the heat treatment.
This high heat treatment also kills the toxins and harmful bacteria and give use clean and sterile perlite for use.
The chemical composition of perlite is depending upon the chemical composition of volcanic glass. Generally, it consists of 70 to 74% silicon dioxide.
The final product gets cavities in it and we call them holes. These holes help perlite to hold nutrients and water content. You can crush perlite soil particles by applying medium force. But when they get mixed in the soil, they do not get crushed. Because the weight of your garden soil is not enough to crush them and they remain in their shape.
aluminum oxide (12-15%)
sodium oxide (3-4%)
potassium oxide (3-5%)
iron oxide (0.5-2%)
magnesium oxide (0.2-0.7%)
How to use perlite in your garden?
You can use perlite in various ways in indoor and outdoor gardens. Some of the basic uses are
Mixing in raised bed soil:
Mix the perlite in raised bed soil to make it loose and lightweight. In some parts of the country, we have tightly packed soil that is not useful for plants. The soil should be loose enough so that the plant roots can develop easily.
Also, dense soil reduces the nutrient absorption rate that directly affects plant growth and health. To make heavy soil lightweight you need to mix perlite in it.
This also improves the aeration and save your plant roots from root rot like conditions.
Add in Container soil:
If the container soil of your garden holds the water for a long time and you are facing root fungus problems. Add perlite to your container soil and make it well-drained soil. Plants need water and carbon dioxide to make their food. But they do not like excess water. Overwatering can damage your plants and they do not grow properly.
For root cuttings:
When we grow plants from cuttings, they need light soil to grow. Perlite gives enough room for new roots to expand to their full natural size. Healthy plant roots mean healthy plants and more yield in the case of vegetable plants.
Types of perlite soil for growing plants
Perlite is mainly of 2 types one is Coarse perlite and the second is fine perlite. Some garden stores sell a third type of perlite that they called medium-grade perlite. But in Actual this is their home-made product. Because the industries only made 2 types of perlite soil.
Coarse perlite soil has high aeration properties and also has good draining properties than another medium grade or fine perlite. If you are growing plants in pots and containers then you should use Coarse perlite. Because it increases the aeration and your plant get enough amount of fresh air. Also, it has good draining capabilities. We all know to save container plants from overwatering we need soil with good draining properties. By adding Coarse perlite to your normal container soil, you can increase its draining power up to 10 times.
The fine grade perlite material is best for starting seeds and growing plants from cuttings. A germinating seed needs a loosely packed growing medium to expand roots. New roots are soft and delicate if they do not get space easily, they will not grow. As a result, your seeds stop sprouting.
If you want to make potting soil for your container plants by yourself. Then the most important ingredient that you need to add is perlite. It is cheap and easily available. You cannot add perlite and compost in same potting soil. Compost also increases the water retention power of soil and make it lose.
If you are using compost do not use perlite or Vice versa.
Perlite Soil Vs Vermiculite Soil
The main difference is Vermiculite holds a high amount of water and nutrients in it. Vermiculite is suitable for plants that required a high amount of water to grow. Because it helps the soil to absorb and hold the nutrients for a long time. This ensures the continuous supply chain of nutrients to heavy feeder plants.
When we grow plants that required a high amount of nutrients, we use vermiculite + Soil. This combination release nutrient at a slow rate. This reduces the wastage of nutrients and also saves your money.
Do not mix perlite and vermiculite together. This will become a useless mixture and a total wastage of money. Both these are soil amendments, add one at a time in your garden soil and make it the best soil for your plants.
Using perlite in hydroponic systems
There is no doubt that perlite is perfect to use for growing plants when mixed with soil. But you can also use it in hydroponics especially when you have plant cuttings. Coarse perlite holds the plant cuttings firmly. Its well-draining nature encourages the roots to develop fast so that roots can touch the nutritional water and absorb nutrients. In hydroponics, water is the main source of nutrients.
Pros and cons of using perlite in your garden
Excellent drainage and aeration properties
Cheap to buy
Useful in hydroponics
Fine grade perlite can be affected by strong airflow
Contains no nutrients
Do not retain much water
Not suitable for growing tropical plants
Best place to buy Perlite
You can buy the perlite from your local garden store. There you can feel the difference between the three types of perlite. But before that check the price of branded perlite on Amazon. Sometimes there is a huge difference in price.
You can also check the difference in local stores and buy the same quality product Online.
Is perlite Organic growing medium?
If you see through the chemistry perspective then perlite is not an organic substance. Because chemistry says any compound found on earth can only be called organic if it contains carbon. If the substance does not contain a single carbon particle then it cannot be called an organic substance.
On the other hand, in the agricultural field, a substance that is naturally extracted or found on earth is called organic. So, for the farming sector perlite is 100% organic and is safe to grow plants. Make perlite soil by using perlite in your garden.