Substrate steaming

Steaming methods

Substrate steaming

Sterilization of loose substrate, using bunkers or containers is a way to steam substrate in large volumes.

The use of superheated steam is one of the most efficient ways of sterilizing substrates. The steaming of a substrate results in a clean, sterilized substrate, ready to re-use.

Advantages of substrate steaming

One of the main advantages of substrate steaming is that it can be applied to smaller or bigger quantities of substrate. The use of containers or bunkers is very common. Konflex has ready to use examples how to build your own concrete bunkers. We can also supply the materials you need, or we can supply you with a mobile container.


How does it work?

We bring in the superheated steam on top of the substrate. On the bottom we use a special suction ventilator to create a vacuum in the substrate. Because of this vacuum, the superheated steam is divided equally throughout the substrate.


In order to work efficiently with large volumes, we recommend to work with several bunkers in a rotating system; one bunker is steaming, while another bunker is being prepared for steaming.

We can help you to decide which method of substrate steaming is the best for your specific situation and will guide you towards the best solution for your situation.

Steaming of large volumes 

Available drawings to build your own steaming bunker

Applicable for smaller of bigger quantities of substrate

Special suction ventilator for equal steam distribution

Preparation before substrate steaming 

Make sure the substrate is dry and loose. If the substrate is loosened and not too moist, the superheated steam can easily penetrate for an optimum result.

Which substrate is suitable for steaming? 

Substrate sterilization can be applied for every imaginable granulate or substrate, for example:

  • Coco peat
  • Rock wool
  • Perlite
  • Pumice stone
  • Tuff
  • Peat moss
  • Potting soil
  • Soil
  • Compost


There are various other steaming methods, for use inside greenhouses, on growing beds, in open field, or compost steaming such as:


More information 

Do you have questions about substrates that you would like to sterilize before re-using it?

Please leave us a message and we will get back to you shortly to discuss the possibilities.

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