The Secret to
Perfect Drainage
Discover Perlite: The volcanic popcorn that saves your plants from root rot and suffocation.
What is Perlite Made Of?
Perlite is made of volcanic glass (specifically obsidian) that has a high water content. When mined and heated to extreme temperatures (1,600°F), the water trapped inside vaporizes, causing the glass to pop like popcorn. This expands it up to 20 times its original size, creating the lightweight, white, sterile granules we use in gardening.
What is Perlite Used For?
Soil Aeration
Its primary use is to break up compacted soil, allowing roots to breathe and water to drain freely.
Hydroponics
It is a popular sterile growing medium for hydroponic systems because it wicks moisture while staying airy.
Construction
Believe it or not, it's also used in lightweight concrete and insulation due to its thermal properties!
How Much Perlite to Add to Soil?
Standard Potting Mix
For most houseplants and vegetables, mix 1 part perlite to 4 parts potting soil (20%). This provides a good balance of moisture retention and drainage.
Succulents & Cacti
These drought-loving plants need fast drainage. Use a mix of 1 part perlite to 1 part potting soil (50% mix) to ensure the soil dries out quickly.
Propagation
Perlite is excellent for rooting cuttings. You can use 100% perlite or a 50/50 mix with vermiculite. The airy structure encourages fast, strong root growth.
Best Perlite Substitutes
Pumice
The closest natural substitute. It's heavier than perlite so it doesn't float to the top, making it great for long-term plantings.
Vermiculite
Use this if you want to retain more water. It's softer and spongier than perlite.
Rice Hulls
A sustainable, organic alternative that breaks down over time, adding organic matter to your soil.
Safety First
⚠️ Dust Warning
Perlite creates a fine white dust when handled, which can be irritating to the lungs if inhaled.
Always wear a mask when mixing large amounts of perlite, or dampen it slightly with water before handling to keep the dust down. It is non-toxic, but avoiding inhalation is best practice.
Perlite vs. Vermiculite
Confused between the two? Remember this rule of thumb:
Perlite
For Drainage
Succulents, Cacti, Orchids
Vermiculite
For Moisture
Seedlings, Tropicals, Ferns