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Is Vermiculite Sustainable? (Important Facts You Should Know)


vermiculite sustainable soil gardening

Our society is based on consumerism. We are able to buy what we need, which ensures us a more convenient lifestyle than our ancestors.

However, when we are so far removed from production, we do not always know what it is we are buying.

This is often the case with vermiculite. In fact, most people have not heard of vermiculite.

However, this does not mean that you have not been exposed to vermiculite.

In order to make informed decisions about vermiculite, it is important to understand the following topics:

  • Definition
  • Uses
  • Sustainability
  • Biodegradability
  • Safety
  • Alternatives

What Is Vermiculite?

Vermiculite is a mineral. In its natural environment, it will have a flake-like appearance.

Its glossy sheen might be gray or brown in color.

Most people think it looks like mica. If you look at the makeup of vermiculite, you will see that it is a silicate mineral made from hydrated magnesium.

Vermiculite naturally occurs in many regions of the world. The main sources of vermiculite include Australia, Brazil, Russia, Uganda and the United States.

Vermiculite is typically mined with an open-cast method since vermiculite is found close to ground level.

Raw vermiculite is treated in order to be more usable in manufacturing. Therefore, raw vermiculite is processed through a heating application.

This process of exfoliation involves large, industrial furnaces.

The result makes vermiculite look almost like worms in appearance. From here, vermiculite has a number of uses.

What Are the Uses for Vermiculite?

Vermiculite is most commonly used in gardening. As a soil additive, vermiculite works like a fertilizer.

In the soil, vermiculite helps seeds germinate while creating a superior soil structure. This is largely related to the nature of vermiculite.

In particular, vermiculite can aerate the soil. It also helps the soil retain water.

This means that vermiculite will not rot when it is added to the soil. Because water is retained, nutrients are also retained.

As a lightweight material, vermiculite promotes aeration. It keeps the soil from settling, which maintains a superior structure for growth over time.

Therefore, vermiculite can help plants grow bigger and stronger.

While gardening is the most common application for vermiculite, it is not the only place where this mineral can be used.

Sometimes, vermiculite is added to animal feed.

When added to feed, vermiculite helps it retain nutrients and moisture. There is no evidence that it is not safe for animals to consume.

Recently, vermiculite has also been applied as a packing material.

Many of the properties that make vermiculite good in the soil also make it good in packaging. It is clean, and it retains its shape well.

In this sense, vermiculite provides aeration for boxes, adding lightweight padding that keeps shipping costs to a minimum.

It is soft enough that it will not scratch delicate items. Moreover, it absorbs moisture well, and it is not particularly flammable.

Vermiculite can also be found in the automotive and construction industries.

In cars, vermiculite is now used for brake linings, gaskets, rubbers seals and paints.

Vermiculite is also used to make boards, plasters, insulation and flooring.

In general, vermiculite is sturdy, and it will not attract pests or deteriorate. It holds up well against heat, cold, sound and moisture.

Is Vermiculite Sustainable?

Vermiculite is a natural substance, but that does not mean it is sustainable.

It has grown in popularity in manufacturing since the 1920s, and it has steadily been applied in new industries over the last century.

To this end, there is no reason to dispute the versatility of vermiculite.

However, there is more reason than ever to assess its sustainability.

Is what we gain from vermiculite more than what it takes to use this mineral?

Because vermiculite is a natural substance, it is found in the ground. The other good news is that vermiculite is not in scarce supply.

That being said, the demand for vermiculite has risen dramatically.

While vermiculite is found all over the world, there are not widespread mines. There are two major mines for vermiculite in the United States.

While watching supplies of vermiculite is important, the amount of energy used to access and process vermiculite is also relevant.

Vermiculite is mined close to the surface, which is better than tunneling, but the process still poses numerous environmental risks.

A lot of energy must be used in the mining of vermiculite.

The picture looks even murkier when you assess the manufacturing process.

In order to make vermiculite usable, it must be exfoliated. Exfoliation requires extensive energy usage since the raw materials must be heated to extreme temperatures.

These facts should make you think carefully about choosing vermiculite.

It is true that vermiculite is durable and versatile, but the number of resources needed to mine and process vermiculite may be too much to justify.

Is Vermiculite Biodegradable?

The story on vermiculite gets even more complex when you consider its biodegradability.

The manufacturing process is obviously a relevant concern, but disposal is equally important. Disposal depends largely on the way vermiculite is processed.

For example, vermiculite fertilizer can be left in the ground for years.

While it is not prone to breaking down completely, it will continue to decompose and release nutrients into the soil.

Over time, vermiculite will release both potassium and magnesium into the soil. It is widely regarded as safe. Some brands are even classified as organic.

Soil with vermiculite can even be used in composting. It is recommended in composting mixes that require ample drainage.

Vermiculite in other forms often requires more care. In particular, there are regulations surrounding vermiculite insulation.

While standard insulation can be thrown in the trash, vermiculite needs special handling.

While some manufacturers have found ways to reuse vermiculite waste, widespread recycling is not available. This also hinders the overall sustainability of vermiculite.

Is Vermiculite Toxic?

Part of the problem with disposal relates to the toxicity of vermiculite.

Vermiculite in its pure form is safe. Indeed, most vermiculite on the market today is very safe.

The reason this can be said with confidence today is that it was not always the case.

Previous mines have been contaminated with asbestos.

This means that vermiculite processed in the 1990s was likely to be toxic. Most of this was traced back to a mine in Libby, Montana.

This mine provided 70 percent of all the vermiculite in the United States. Obviously, upon this discovery, the mine was shut down.

Today, vermiculite is thoroughly tested. This ensures that any vermiculite you buy now will be non-toxic.

It will not contain known carcinogens. This is why many brands are certified organic.

However, many homes still have vermiculite insulation. Homeowners may not even be aware of this fact.

In general, vermiculite insulation is only dangerous when it is exposed.

If you are going to replace your vermiculite insulation, you must take certain safety precautions.

Asbestos is most dangerous when inhaled or when it comes into contact with the skin.

Therefore, you must use safety gear before putting the insulation into bags.

Then, you must contact your local waste disposal provider to complete disposal. Do not be in areas of the home where vermiculite insulation is exposed.

The EPA has deemed all gardening usages of vermiculite to be safe. However, it is recommended to only use it outside or in ventilated areas.

Finally, there is some concern regarding vermiculite in the manufacturing setting.

Although most vermiculite does not contain toxic substances, it can still create dust in the mining process.

This dust is known as silica. When silica is inhaled, it can cause lung inflammation and disease.

Workers can develop silicosis, which is a deadly and incurable condition.

Manufacturers can take measures to protect workers. These measures are absolutely imperative to avoid risk from vermiculite.

What Can Be Used Instead of Vermiculite?

There are many good reasons to hesitate about using vermiculite.

Despite its benefits, vermiculite is not the only option. There are plenty of other, more sustainable options for most of your projects.

For gardening, some people use perlite. Perlite is a volcanic glass that can be mined and processed for soil enrichment.

While it is an alternative to vermiculite, it is not necessarily a more sustainable one.

If you are looking for something with a less noticeable environmental impact, consider more sustainable options.

For example, you could use coconut husks.

Known as coir, these shredded husks can safely be added to soil mixes for improved growth.

Because husks are a byproduct of the coconut harvest, they renewable and safe.

Other plant hulls may also serve a similar function. Look into hulls from rice, peanuts or other nuts.

Hulls are irregularly shaped and decompose slowly, which ensures a light texture and longstanding nutritional impact.

You could also look at various versions of compost. Many composts are excellent for potting soil.

To meet specific needs, consider distinct composts made from cotton gin waste, mushroom byproducts and more.

In terms of other applications, vermiculite is easily replaced with other materials. It is no longer used in insulation.


Overall, while vermiculite can be used safely, the case for its sustainability is not convincing.

When you look at how many other options are available instead of vermiculite, it may not be necessary to make the compromise.

If you are going to use vermiculite, then be sure to learn about where it comes from and how to use it properly for the best results.

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