Perlite vs Vermiculite

You’re attempting to select between vermiculite and perlite in the garden center. All you recall is that one resembles little Styrofoam balls.

These two are not the same things, common perception. Vermiculite is a brown or beige-colored silicate substance with a soft, sponge-like feel. Perlite is a harder volcanic rock that is white in color and is mined.

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They both are natural soil additions that strengthen soil structure in comparable ways, but there is one significant difference between the two that may make or break a gardening operation.

Perlite vs Vermiculite

The distinction between vermiculite and perlite is critical for the success of your vegetation. They appear to be extremely similar, yet they differ in a few key areas. Let’s get into the specifics and clear up any misunderstandings.

What is Perlite?

It may be described as “popped” natural glass. The quick cooling of lava produces that glass, which may be any of a number of hues in its natural condition.

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When obsidian comes into touch with water, it forms a unique sort of volcanic glass with high water content.

Perlite is made by shattering and superheating obsidian, a volcanic glass that forms when lava cools quickly and comes into touch with water. The final result is a porous, amorphous, and stiff material.

The end result is a light, porous material. As a result, it’s great for forming drainage channels for potting soil without adding too much weight, as sand may. Perlite is available in fine to coarse grades as well.

How Does It Look Like?

When crushed, it is a white grain that is smaller than vermiculite and starts off as airy balls or powder. The grain size varies based on whether you want a finer or medium grade, which are the two most popular options.

Is Perlite Organic?

Organic molecules, from a chemical standpoint, contain carbon. Perlite is classified as an inorganic substance since it does not include carbon.

However, in the context of gardening, “organic” refers to material that is created organically without the use of synthetic procedures or major chemical alterations.

True, perlite must be “popped” in an industrial process to become the lightweight material we know and love, however, it is a natural mineral that is mined from the soil.

Properties of Perlite

Following are the properties of perlite:

  • Air porosity
  • Grain stability
  • Low density
  • High water storage capability
  • Heat insulating
  • Sound-proof
  • Resistant to moisture
  • Non-combustible
  • Safe against vermin
  • Rot-resistant
  • Eco-friendly

Uses of Perlite

Perlite is most commonly associated with gardening, but its lightweight and other beneficial features enable it to play an essential part in a variety of sectors.

  • Gardening

Perlite aids in the decomposition of clay soils. It’s also used as a soil addition in gardens to enhance soil structure. It’s used as a stand-alone product in hydroponic gardening installations to root cuttings, anchor/support root systems, and germinate seeds.

  • Filtration

It is increasingly being utilized in a variety of applications to filter particles from liquids. Stormwater discharge from highways and roads is filtered with it.

  • Construction

For insulation, perlite is utilized as a loose material in hollow masonry walls or concrete blocks.

  • Manufacturing

It’s also found in lightweight plasters and concrete, acoustic sprays, and ceiling tiles to mention a few applications.

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Types of Perlite

Horticultural perlite is divided into four categories based on particle size after heating and expansion: super coarse, after which comes coarse, then medium, and finally fine grade.

  • Super Coarse Perlite

This type of perlite has particles ranging in size from 14 to 3/32″ and has a 19% water holding capacity. Because of the particle size, it isn’t as popular in gardening as it creates the optimum porosity for drainage and aeration.

  • Coarse Perlite

With a 34 percent water holding capacity, it comes in sizes ranging from 3/16 to 3/64″. It provides an excellent blend of drainage and water holding capacity, making it an all-purpose grade.

  • Medium Grade

It’s a midway ground between coarse and fine grades, with sizes ranging from 1/8″ to 1/32″. It can contain 46 percent of water and is best used alone as a growth medium for potted plants and seedlings.

  • Fine Grade

This form of perlite contains the tiniest particles, with fragments ranging from 1/16 to 1/128″. It’s great for rooted cuttings and beginning seeds since it can contain 52 percent of their weight in water.

How to Use Perlite for Gardening?

Perlite is often used in soilless mixes and potting soil, especially for indoor seed starting, as it helps in keeping the soil structure flexible and well-draining without the risk of compaction.

  • For a clean, basic seed starting mix that encourages healthy seedling development and avoids damping-off disease, mix equal parts of vermiculite, peat moss or coco coir, and perlite.
  • You can also use it for propagating plant cuttings. You may root your plant cuttings in a small jar filled with moist perlite other than only water.
  • You may enhance drainage in raised beds or in-ground garden beds with cakey clay soil by raking a 2 inches layer of perlite further into the top 6 to 12 inches of soil while amending the soil with compost including other nutrients.
  • Perlite is also commonly used in drier cactus, orchid, and succulent planting mixes, as well as in hydroponic settings as a stand-alone growth media.

Benefits of Using Perlite in Gardening

  • Even in thick or moist soil, it is structurally stable and preserves its form.
  • There are no hazardous chemicals or additions in it.
  • It can absorb water while allowing the remainder to drain freely.
  • As it doesn’t degrade, it’s suitable for use in gardening mixes for plants that only need to be repotted once in a while.
  • It has a fantastic aeration system. Aeration is critical for proper root development since plants absorb 98% of their oxygen through their roots.
  • In the soil food chain, airflow supports beneficial nematodes, earthworms, and other beneficial organisms, which in turn promotes plant growth.
  • Because of its neutral pH, it may be used in any container or garden bed.

Advantages and Disadvantages of Perlite

Perlite, like so many other things, has both benefits and drawbacks as a growth medium. The benefits considerably exceed the disadvantages in this scenario, promoting its appeal in the horticultural business.


  • Minerals required for plant development are naturally present.
  • Because of its sterility, it is ideal for seed beginning. Root rot and damping-off are unlikely to occur.
  • When blended with other components, neutral pH does not need to be changed, nor will it change the total pH.
  • Because it does not degrade, it may be used year after year.
  • Easily accessible and simple to produce.
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  • Perlite may be blown and floats in extra water due to its lightweight.
  • This is a nonrenewable resource.
  • Dust can irritate the eyes and cause breathing difficulties.

Does Perlite Decompose?

Because perlite is formed from superheated volcanic rock, it does not disintegrate over time. If you add perlite to the soil, it permanently alters its texture and improves its suitability for plant growth.

What is Vermiculite?

In more aspects than one, vermiculite is a “flakey” clay mineral. It’s formed by exfoliating mica, which is a sheet silicate mineral, then breaking it apart and superheating it. The end product is a spongy, squishy hydrous substance with plate-like, flat flakes.

In your soil, it interacts with potassium, calcium, and magnesium. It also helps to gently boost the pH of your plants, despite the neutral pH of 7.0.

How Does It Look Like?

Vermiculite has a golden brown to dark brown tint that might be difficult to distinguish from the potting soil it’s blended with. Vermiculite flakes stretch into a worm-like form when water is introduced, acting like an absorbent sponge.

It’s difficult to see the difference once it’s blended into the soil, especially when the tint darkens when moist.

Is Vermiculite Organic?

Vermiculite is sometimes organic, but not usually. Vermiculite is a natural mineral that is mined, heated, and packaged for use by gardeners. Vermiculite is organic when it is mined and processed organically.

Uses of Perlite in Gardening

  • Vermiculite can be used alone or in combination with compost or peat to condition and brighten the soil. This will hasten the formation of delicate young root systems and enhance anchoring.
  • Root cuttings can be placed immediately in medium-grade vermiculite. Simply wet the cutting and insert it up to the node.
  • Vermiculite as a growing medium also allows the plant to absorb the potassium, ammonium, magnesium, and calcium it needs to thrive.
  • For seed germination, you can use vermiculite alone or in combination with soil or peat.
  • Fill a container with vermiculite and place root or bulb vegetables inside. The vermiculite’s sponge-like nature will absorb any excess moisture as it helps in preventing rot or mildew while also protecting them from temperature changes.

Types of Vermiculite

There are two basic types of vermiculite.

  • Crude Vermiculite

The mine’s raw vermiculite is made up of golden/brown/silver flakes that are meticulously sorted into five categories, each with a different range of particle sizes. Crude Vermiculite has a loose bulk density that varies by grade but is normally between 700 and 1050 kg/m3.

  • Exfoliated Vermiculite

In the commercial exfoliation process, crude vermiculite is passed through a heating chamber in a controlled way. The raw vermiculite then spreads at right angles to the cleave planes, resulting in concertina-shaped particles with a volume several times that of the original.

Benefits of Using Vermiculite

  • Professionals use soil with medium-grade vermiculite for the majority of horticulture chores, including cutting insertion. You don’t have to worry about over-watering because the container has proper drainage. This dirt will stimulate faster root development than normal soil.
  • Mixing in a little vermiculite dirt provides air passages that help the soil breathe if the soil is sticky or thick.
  • Vermiculite soil addresses the problem of compacted soil seen in many flower pots. This will give excellent moisture and air management, as well as lighten and aerate the soil and let the roots spread out in the container, necessitating less watering.
  • Mulching roses, dahlias,  shrubs, tomatoes, and garden plants with a couple of inches of vermiculite soil keeps them from withering out and insulates your plants against cold weather.
  • It protects the roots from the wind and sun and offers even moisture regulation, resulting in healthier plants when used on topsoil.
  • Fill your container halfway with vermiculite dirt and smooth down the top. This style of the floral arrangement will keep the flowers fresh for days without having to worry about water spills.
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Advantages and Disadvantages of Vermiculite

As we all know that everything has advantages and disadvantages, and it is true for vermiculite as well.


  • It is lightweight and has excellent compressive strength that makes it perfect for use in containers.
  • You can recycle it very easily.
  • When exposed to heat and humidity, it swiftly degrades the environment.


  • Fungus and bacteria can thrive in the damp climate, wreaking havoc on the plants you’ve produced.
  • Vermiculite can be costly and difficult to come by.
  • Unsustainable.

Does Vermiculite Decompose?

When used in potting soil, vermiculite does not break down or degrade. As a result, vermiculite is a long-term approach to repairing and enriching your soil.

Can You Use Perlite with Vermiculite?

There’s no reason to combine vermiculite and perlite because they’re best used in separate scenarios. Perlite can be used to root cuttings or to grow cacti, epiphytes, succulents, and some other plants that benefit from aeration and fast drainage. Perlite may also provide a boost of humidity to plants that require it. Vermiculite is superior for beginning seeds and other conditions where plants need a steady supply of moisture in their soil.


People would argue they are the same at the end of the day, and I would agree in the most generic sense. You won’t hurt any plants or veggies if you use them in the right proportions. However, you can use 100% of either and be fine, but your plants would lack access to all of the nutrients and minerals they require.

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