Learn more about perlite, when to add it to soil, and how it is used in hydroponics.
What Is Perlite?
It forms as molten volcanic lava slowly cools and contains silicon dioxide, aluminum oxide, and other minerals.
The Spruce / Krystal Slagle
It’s also widely used in the beverage industry as a filtration agent.
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Types of Perlite
Perlite is sold for industrial, construction, and horticultural use.
When purchasing perlite for gardening, it is important to pick the correct form and grade.
The most common grades used in horticulture are coarse, medium, and fine.
Selection depends on the throw in of plants you are growing and the soil you are using.
Perlite is sterile, lightweight, and doesn’t change the soil pH.
It can be reused often as long as the soil is free from diseases or pests.
If you enjoy or want tostart hydroponic gardening, perlite can be used as a growing medium.
How to Use Perlite in Gardening
Perlite has many advantages in gardening.
Here are just a few ways it can be used to help your plants.
Improve Soil Drainage
Adding perlite to soil helps prevent soil from forming clumps that impede water drainage.
Proper drainage helps prevent root rot and fungal soil diseases.
Perlite can be mixed directly into freshly tilled garden soil or added to potting soil mixes.
Improve Air Circulation in Soil
Plant roots need oxygen to thrive.
The shape and structure of perlite create pockets in the soil that improve air circulation and prevents compaction.
Add one gallon of moistsphagnum peat mossand one gallon of perlite.
Mix well to create a loose mixture for filling containers.
Store in a covered container.
Store in a covered container and moisten the mixture well before adding to seed starting flats or pots.
Hydroponic Gardens
Perlite offers insulation against temperature fluctuations in hydroponic systems.
What Are The Differences in Perlite and Vermiculite?
While both perlite and vermiculite help improve drainage in soil,they perform differentlyfor moisture retention.
Perlite holds some water in its crevices, while vermiculite absorbs water like a sponge.
Disadvantages of Perlite Use
Just as with any product, there can be issues when using perlite.
Perlite is very lightweight and can float to the top of soil mixtures if it is not combined well.
Perlite and sphagnum moss, though similar in their functions, provide different benefits.
Most soil mixes will benefit from the presence of both.
Perlite toxicology and epidemiology.Maxim LD, Niebo R, McConnell EE.
National Center for Biotechnology Information.
