Benefits of Substrates in Soil and Soilless Mixes

And the Use of Perlite and Vermiculite

Soil and Soilless Mixes

In soil and soilless mixes, a substrate is an additional substance incorporated to aid growth. While soil mixes are a common choice, soilless mixes also provide benefits. As the name suggests, soilless potting mix does not include the use of soil. Instead, plants are grown in a variety of organic and inorganic materials. Some growers prefer this method because it prevents the transfer of diseases that may be present in the soil.

Benefits of Substrates in Soil and Soilless Mixes

As different as soil and soilless mixes are, the use of substrates benefits both of them the same way. Two popular and effective substrates are perlite and vermiculite⁠—both inorganic minerals.


Perlite is formed by molten (magmatic) rock, also known as volcanic glass. When it is heated rapidly in industrial furnaces, the volcanic glass softens, causing the entrapped water molecules to turn to steam and expand the perlite particles—much like popcorn. Expanded perlite is a popular choice for soil and soilless mixes because it:

  • Improves aeration
  • Is free of organic contaminants, which helps prevent disease
  • Is pest-proof
  • Doesn’t expire or lose its properties over time

Plus, it is lightweight, making it easy to work with and easily mixed with other mediums.


Vermiculite is a hydrated magnesium aluminum sheet silicate mineral closely related to mica. This mineral is a top choice for horticulturists because it acts as a sponge for nutrients and then slowly re-releases them back into the soil, aiding the growing cycle. Benefits of vermiculite as a substrate includes:

  • Improved aeration
  • Moisture retention
  • Faster root growth
  • Retains and re-releases nutrients like potassium, calcium, and magnesium

Also, vermiculite is lightweight, making your soil and soilless mixes easier to work with.

Perlite as a Substrate in the Cannabis Industry

Cannabis plants, in particular, thrive with perlite as a substrate because the glass-like bubbles in the perlite encourage drainage and ensure oxygen is provided right to the plant roots. When perlite is mixed with soil, it creates an oxygenated environment, allowing for faster draining and the opportunity to feed your plant more fresh, essential nutrients.

It is important to choose the “Goldilocks” size of perlite for your cannabis growing. While it might seem like larger perlite ores are the best choice, these big kernels can actually break when in transit, and you’ll end up with large ores mixed with dust instead. For cannabis growing, a medium-size ore is the most effective because they are sturdy and reliable.

To use, simply mix two parts soil to one part perlite for increased drainage and oxygen at the root zone.

Choose Dicalite Management Group for Your Soil and Soilless Mixes.

At Dicaperl, our perlite ore produces a large grade expanded product that is harder and more consistent, so when you open your bag, you can expect kernels—not dust. You’ll find this durable horticulture perlite and vermiculite is “just right” for your growing needs. Call us today at 866-728-3303 to request your free sample.

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Our blog offers insight and information about new and exciting uses for perlite, diatomaceous earth, and vermiculite deriving from years of research and application. From passive fire resistance to mineral depth filtration, by subscribing to our mailing list, you will receive the latest information surrounding the Dicalite, Dicaperl, and Specialty Vermiculite brands and products.

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