Recently, during a discussion with a fruit nursery, they mentioned having a “fifth-generation greenhouse.” This statement puzzled me because conventional wisdom suggests that such greenhouses are not suitable for nurseries. The explanation provided was that they indeed have modern greenhouses.
This encounter made me realize the urgent need for clarifications regarding the classification of greenhouses, and I believe that this blog on EastFruit will contribute to addressing this issue.
The concept of dividing industrial greenhouses into “generations” was introduced approximately ten years ago by the Russian company Fito (now LIS) to promote semi-closed greenhouses. This classification is widely used among greenhouse specialists in Russia and other post-Soviet republics but remains relatively unknown in other parts of the world.
Greenhouses across the globe are categorized based on various criteria, including whether they are self-designed or industrially manufactured, the type of cover used (glass or plastic), design (free-standing or multispan), heating method (solar or additional heating), heating system (air or water), use of artificial supplementary lighting, and technological level (low or high tech).
To maximize profits, investors need to construct and design greenhouses tailored to provide optimal conditions for specific plant species. One noteworthy example is Houweling’s Tomatoes in Canada, which strategically built a greenhouse to prevent external pest infiltration, reducing the need for pesticides. This Ultra Clima greenhouse minimizes ventilation windows, maintaining slightly increased air pressure to keep insects out.
The second generation encompasses glazed greenhouses designed for year-round use.
The third generation includes structures known as “anthracite,” named after the Ukrainian city where they were produced during the Soviet era. These greenhouses were replicas of Dutch Venlo blocks from the seventies, and today, they are nearly extinct. These anthracite greenhouses had a ridge height of 4 meters, and cultivation primarily involved plants grown directly in the ground.
The fourth generation comprises contemporary Venlo greenhouses, standing at a height of 6-7 meters. These greenhouses, named after the Dutch city where they originated, utilize computerized control for managing microclimate conditions, implementing shading and energy-saving screens, and incorporating hydroponics. Presently, this represents the predominant high-tech industrial greenhouse model in the Northern Hemisphere. The choice of coating material, whether glass or film, is not a decisive factor in this context.
Semi-closed greenhouses, categorized as the fifth generation, have gained prominence for their ability to significantly reduce energy costs and enhance productivity and product safety. However, their higher investment costs make them less suitable for nurseries and organic farms where plants are grown directly on the ground or tables.
The concept of “Growing in a New Way” has emerged, initially designed for semi-closed greenhouses but found applicable to traditional modern greenhouses. Heat recovery systems, a more cost-effective alternative to semi-closed greenhouses, have entered the market. These systems blend warm indoor air with cold outdoor air, reducing energy costs but necessitating a shift in cultivation practices.
The question arises: are fifth-generation greenhouses necessary everywhere? The experience in Central Asia demonstrates that in certain climates, achieving yields comparable to temperate countries is challenging without specialized greenhouses. Factors like lack of natural light in winter and overheating in midsummer require innovative solutions, such as pad-and-fan cooling.
In regions like Western Europe, Moldova, and Ukraine, a surge in energy prices has prompted owners of modern high-tech greenhouses to pause year-round cultivation, leading to periodic market oversaturation but reducing energy consumption.
Ultimately, the evolving landscape of greenhouses, influenced by factors like labor shortages and rising energy prices, underscores the importance of continuous technological advancements. As the technological level of greenhouses rises, so must the expertise of agronomists and greenhouse owners to ensure the viability of their investments.