Energy-efficient practices in organic greenhouses

Greenhouse horticulture is an intensive cultivation system that also produces crops outside the growing season and in every type of climate. In the recently started three-year CORE Organic Cofund ERA-NET project 'Greenresilient', a more agro-ecological approach is being taken in organic greenhouse horticulture. The emphasis is different for each sub-region: in the Mediterranean Sea area they are aiming for the use of plant protection products, also on less use of copper as a fungicide. The Northwest European climate belt focuses on energy-efficient systems to produce at low outdoor temperature and low natural light.

Acquiring high-quality and tasteful vegetables from greenhouses is technically challenging, especially if you are aiming for unheated energy-efficient greenhouses from polytunnels. Especially if you want a production system that is sustainable, local and agro-ecological. Greenresilient will help to keep a high and stable production, but with a lower impact on the environment. To this end, robust, locally adapted agro-ecosystems are designed for organic greenhouse horticulture.

Experiments are planned in five countries (namely France, Italy, Denmark, Switzerland and Belgium) at companies and practice centers, in which the growing system that is now commonly used (business as usual or BAU) is compared with more innovative cultivation systems (INN) based on more diversity in crop rotation and a set of agro-ecological measures that must achieve greater functional biodiversity.

At the same time, a Life Cycle Assessment (LCA) is planned to assess the ecological sustainability of the different biological protected systems. "We calculate the environmental consequences of two "extreme" strategies, BAU and INN, for the 5 experimental sites in the project."

In Flanders, the organic acreage increased to almost 7,000 hectares in 2016, an increase of 30% compared to 2015. The share of organic in the Flemish agricultural area is 1.1%. The organic greenhouse in Belgium is about 1% of the total vegetable cultivation, in the Netherlands it was around 2.5%.

ILVO and PCG are Flemish partners. ILVO researches the aspects of soil fertility, nutrient management and functional biodiversity in the renewed cultivation systems. PCG is one of 5 experimental sites where innovations are tested and evaluated.

Justine Dewitte (PCG): "Both the European and the Flemish organic sector continue to grow and the interest in organic farming is also increasing. Market demand is on the rise, the biggest challenge for us is realizing winter production in unheated or low-energy greenhouses."

Koen Willekens (ILVO): "The use of agro-ecological practices in organic protected cultivation is a very innovative and an alternative to an often intensively traditional production system."

The Italian CREA (Council for Agricultural Research and Economics) coordinates the project. Project coordinator Dr. Fabio Tittarelli: "Greenresilient works very multi-disciplinarily: specialists in agriculture, botany, agroecology, soil chemistry, entomology and plant diseases from twelve research centers in eight European countries are involved."

In Flanders, ILVO and PCG have divided the work as follows: on PCG they test specific, frost-resistant winter crops, with flower margins in and outside the tunnel, with mixing of crops for disease suppression and with the use of green manure and compost for better soil fertility. ILVO conducts the soil and crop analyzes and controls the entire soil management.

In April 2018 the project was launched in Capua, Italy. The hope is that in three years' time, at the end of the project, there will be more insight into the potential and feasibility of agro-ecology in the organic protected cultivation practice in Europe.