Since ReduHeat was introduced in 2005 many growers have asked us if it’s possible to combine the different shading products. Just to make it clear, when we talk about combining we mean “layering” products over each other, not mixing them because that would achieve nothing. With the arrival of new diffuse coatings such as ReduFuse and ReduFuse IR the question has arisen again. So what is possible and is there an advantage?

Combining shading products provides the opportunity to shade according to light intensity over the course of a year. Crops coming out of a dark winter period are often exposed to strong solar radiation in February. Usually this is still too early to apply a product such as ReduSol because it removes too much light on cloudy days.

A few years ago we did some trials with a combination of ReduHeat and ReduSol during a shading season. ReduHeat was applied to the greenhouse roof in February and provided the crops with the initial protection against the bright sun yet it still allowed sufficient light to enter the greenhouse. A few months later a thin layer of ReduSol was applied over the ReduHeat to protect the crop during the warm sunny summer days.

ReduHeat has the positive characteristic that it allows the majority of the PAR light to enter while reflecting heat radiation (IR). The application of a thin layer of ReduSol over the ReduHeat doesn’t alter this property, but it does lower the entire shading ability of ReduHeat (see graph). The sun (UV light) and rain gradually wear away the thin layer of ReduSol but they have little effect on the ReduHeat coating underneath. As a result a layer of protection still remains for any warms days that follow in the late summer months of August and September.

This strategy is very effective for plants. As summer approaches, the plants receive more and more protection and still enough light during the season to develop. Another advantage is that there is less need to use artificial lighting on cloudy spring days because enough light enters the greenhouse.

It is possible to combine all the ReduSystems coatings made by Mardenkro, with ReduSol always as the second layer (first ReduSol and then another coating on top is of little use). All products are removed at once with the same cleaning agent, ReduClean. In addition, we advise growers not to combine products from different manufacturers because this interferes with their removal.

For more information