In soilless growing, instead of using soil you use a hydroponic grow medium or substrate. These substrates are used to support the plant’s root system and hold them in place by supporting the weight of the plant. These substrates also retain moisture and provide oxygen to the plant’s roots.
Unlike soil which generally contains fertilizer in it, hydroponic substrates are inert and therefore need a nutrient solution added to them to boost plant growth.
Here are four of the most common forms of hydroponic substrates used in soilless growing.
4 Hydroponic Substrates
- Clay Pebbles