Steaming has plenty of advantages, which all have direct positive effects on soil, plants and hence yields.
For more than 100 years alternative pest management has been used. In the 1990s methods to optimize the application of steam were developed which have been gradually established.
Steaming time, energy consumption and effectiveness
Among these innovations, integrated steaming, partial steaming and sandwich steaming must be mentioned. All these innovations of steaming technology have the goal to reach the highest possible effectiveness in reducing energy and steaming time. They can all be used simultaneously.
The biggest issues of steaming are the relatively high energy and time needed to generate steam and induce steam into soil to the required depth to yield desired results. Hence in early days only small areas could be treated with steam.
Sandwich-Steaming in combination with the application of fully automated carrier technology has been a considerable break-through in large area steaming. Through the injection of hot steam from above and underneath the ground more than 120 kg of hot steam can be brought out per m2 and hour. Besides the considerable time savings that occur due to the quick induction of steam, heat losses due to thermal conduction are optimally reduced. Depending on the size of the steam generator in less than 5 minutes areas up to 20 m2 of size can be heated down to 20 cm depth in just 5 minutes reaching temperatures of up to 95°C.
Hence it is possible – on open fields or in green houses – to quickly steam and optimally prepare areas up to several hectares in size for cultivation without chemicals.
Due to the steadily increasing cost for oil and gas since the 1960s, it was necessary to develop solutions which encounter high energy consumption of steaming methods. Steaming should be limited to areas in which the cultivated plant solely grows and should not include unused areas, such as space in between plant rows. Partial Steaming was successfully developed and put into practice. In heavily disease-ridden soils the risk of recontamination from not treated neighboring areas was very high.
A solution of these previously mentioned issues was the development of Integrated Steaming. It’s goal being to reduce disease pressure on decontaminated soil by injecting active micro organisms right after steaming. Hence phytopatogenic organisms are hindered to resettle.
Today all three mentioned methods, Sandwich, Partial and Integrated Steaming can be combined to reach maximum efficiency.