Pioneering Hydroponics

Since 1976

What Type of Media Should I Use for My Grow?

When we refer to media we’re talking about what you put into your pots for your plants to grow in.
Media comes in different forms and supports plants in different ways, which is why there are many types.

Why use media?

There are different reasons for using media which include:

-          Supply roots with the water nutrients and air they need

-          To provide an environment where roots can thrive

-          To support plants as they grow taller


There are two key measures of media when it comes to choosing which is right for your needs.

Air Filled Porosity (AFP) and Water Holding Capacity (WHC).
AFP refers to the amount of air that is available to your plants. Whereas WHC refers to the amount of water that your media can hold.

A media with a higher AFP means that you have pockets of air available, which give you the chance to cultivate a healthier root system and ultimately a higher-yielding plant.

Different types of growing media


The most well-known media, and still a firm favourite. Probably because it holds the most moisture of any of the media types we discuss in this piece.
This creates a buffer that means that you’re not over reliant on your watering system or gaps in time you can’t get to your plants to water them.

The moisture retaining nature of Soil, though means that there are fewer pockets of air available for your roots to thrive.

Soil though is a media that allows for beneficial bacteria and fungi to thrive, which help the plants that they’re supporting.

Soil is the perfect media for novice growers. But, if you are growing organically, make sure that your soil indicates it contains only organic materials.


Coco coir is a growing media used by an increasing number of growers. It consists of fibrous coconut husks and can be mixed with clay pebbles to increase the air availability for plants roots.

Coco allows you to create an environment that allows beneficial microbes and additives to thrive. This speeds up growth rates while improving flavours.

It still has moisture retaining qualities, but as it drains more freely than soil, there’s more air availability for your plant’s roots.

Additionally coco is the natural choice for growers looking to move from soil and improve their crop, without losing the buffer that can sometimes help save a growers plants.


Both Coco and Soil are perfect for growers who like to hand water their plants.


The media of choice for growers looking for superior yields and one that is often used with hydroponic systems.

Clay pebbles provide air gaps between each pebble and allow for free drainage. Therefore, oxygenation is superior to that of coco and soil.

You’ll find that there are clay pebbles of different sizes and shapes, which slightly affect how they’ll support your plants.

Those that are perfectly spherical tend to be less porous and retain little moisture, which means there is no buffer for your plants.
Uneven pebbles have higher water retention than regular clay pebbles and can mean that you need to feed slightly less often.

The difference between the two types is easily distinguishable to see, so don’t worry about choosing the wrong version.


Offering the best of both worlds, mixed media like 60/40, which is a combination of Coco and pebbles have a good WHC and AFP. This is why more growers are looking at this combination for their crops. It has become particularly popular with growers who use dripper systems like Wilma or Flood & Drain variations of IWS.


This light material provides moisture retention via its fibrous structure.

Available in small cubes it allows quick drainage and lots of space for air to provide oxygen for the roots.
Many growers like to mix rockwool with other medias, like clay pebbles to increase moisture retention.

Whilst light and easy to handle it also is unable to provide 100% support to large plants. 
Largely used in NFT systems, roots can freely grow through the rockwool, but as the plants grow taller they’ll need additional support.

If using only rockwool to support plants, be careful not to overwater as the moisture retention is very high.




 So, that’s our overview on different types of popular growing media.

Ultimately, the only true ‘hydroponic media’ is water. Hydroponics refers to growing in water with nutrients added and any grower looking to develop should have this as their end-goal.
The goal is to get the best result from your plants possible and if you achieve that from soil, then that’s the way to go.

If you have environmental concerns and would like to reuse your media, then Clay pebbles allow you to do this.
To do this we recommend using an enzyme that breaks down dead roots and plant matter when cleaning your pebbles.