Our Guide to Growing Media

Different growing mediums provide plants with different environments for each plant and grower’s needs.

When deciding what plant medium you want to use, you need to think about the amount of drainage you need, the nutritional content of the medium, and how forgiving the media is? The choice of growing media will affect the choice of grow system used so can seem a little ‘chicken and egg’. Many people have a preference for the type of medium they like to grow in and therefore then pick an appropriate system to use, others have a particular grow method they like to use and hence choose a media that suits that method.

Here are the properties of the main four growing mediums: 

Soil 

Soil is an affordable and easy-to-use medium; it’s an all-natural resource that is very popular amongst beginners and professional growers. This is the most forgiving media; the soil contains microbes that can help to fight pathogens, and nutrients that can help to keep your plants healthy. Soil compacts which keeps the roots insulated meaning temperature changes are less likely to affect the roots. 

Coco

Coco is an organic growing medium made from grinding up the husks of coconuts. It is a renewable source that is easy to use and can be reused. When using Coco you will have to supply all the nutrients to your plants to keep them healthy, this gives you more control over what nutrients your plants are getting.

Coco creates a light airy structure which is great for the growth of the roots as it provides them with better access to nutrients and air. Similar to soil, Coco insulates the roots meaning the roots shouldn’t be affected by slight temperature changes.

As Coco doesn’t have its own nutrient supply means that you will have to provide nutrients from the start and make sure you are constantly monitoring the amount of nutrients needed and given to the plant. 

Rockwool

Rockwool is a porous hydroponic grow medium; it is made by melting rocks, spinning them into thin, long fibers that are then pressed into cubes. Before using the Rockwool you have to ensure you have balanced the pH level. It is important to not squeeze the Rockwool and reduce the airflow for plant roots.

Rockwool can be harmful as the fibres and dust can irritate your eyes, nose, and lungs, this can be avoided by soaking it in water. The high pH of Rockwool means that you have to take the extra step to balance it so it’s safe to use on your plants. 

Clay Pebbles

Clay Pebbles are made from expanding clay, their shape ensures they do not compact and creates a draining effect. They provide great support for the plants to grow and can be cleaned and reused.   They hold a neutral pH and do not release any nutrients into the water which means you have complete control over what or how much nutrients your plants are getting. 

The clay pebbles have a poor water holding capacity meaning that they drain and dry out quickly so a constant water supply is needed to prevent roots from becoming dried up.