Greenhouse cultivation involves growing crops inside structures covered with a transparent material that protects from extreme weather and unfavorable climatic conditions.Korea has an active greenhouse farming culture, accounting for about 12 percent of agricultural output by value.Korea produces various fresh vegetables, flowering plants, and fruits in greenhouses in what is known as “controlled horticulture” or “greenhouse farming”.In the past, Korea’s controlled horticulture industry played an important role in supplying fresh agricultural products throughout the year for the domestic market.Now the objectives of greenhouse industry is producing more high quality and value-added fresh produce for export markets, supplying safer foods to consumers, and maintaining stable prices for the Korean agricultural market.The output of the controlled horticultural industry in Korea increased by six times to 5.3 billion USD in 2016 from only 760 million USD in 1990.Notably, the growth of vegetable output in controlled horticulture increased eight times during the same period (over 26 years)The output of flowering plants only doubled during the same period due to the reduced demand since 2008 (world financial crisis) and the lower profit ratio compared with other crops.In 2016, the output of controlled horticulture accounted for 12 percent of total agricultural output (45 billion USD).The Korean controlled horticulture industry is heavily dependent on plastic greenhouse production.

      There is some glass greenhouse production for products such as paprika and tomatoes.Korea’s total arable land declined gradually from 2.1 million hectares (Ha) in 1990 to 1.64 million ha in 2016 due to the following changes in the Korean rural sector: 1) reduced farm population and increased aging population causing farmers to give up farming, 2) expansion of urban development and increased property value near urban areas, 3) lowered local agricultural competitiveness resulting from an increasingly open market.On the other hand, the area of controlled horticulture increased to 105,758 hectares (ha) in 2000 from 44,613 ha in 1990, as a result of the government support program for facility modernization (greenhouse) for controlled horticulture which ran for 21 years (1991 – 2012).In 2016, the controlled horticulture area increased due to  1) the government support program, 2) demand increase for fresh agricultural produce including vegetables and fruits during the winter season, 3) expansion of the urban population and increased demand for fresh produce due to an increase in disposal income.

        In the 1970s, the industrial development period in Korea, the area for greenhouse production located near urban areas increased rapidly due to the resulting increased demand for fresh produce during the winter season caused by the expansion of the urban population.In the 1980s, the demand for fresh vegetables increased due to the increased interest and understanding of diet that accompanied Korean economic development.In the 1990s, Korean greenhouse production developed with the introduction of modernized horticultural facilities.Investment increased along with government support programs designed to help farmers adjust to the agricultural market opening.In the course of this century, the area for controlled horticulture decreased gradually due to the end of government support programs in 2012.In 2016, the area of fruit-bearing fruits and vegetables accounted for 50.2 percent (41,979 ha) of total greenhouse area (83,629 ha) followed by leafy and stem vegetables with 9.9 percent, 9.3 percent for fruit trees and 2.8 percent for flowering plants.Within the greenhouse area dedicated to fruits and vegetables, Korean farmers grow watermelons the most followed by tomatoes and strawberries.For greenhouse leafy and stem vegetables area, Korean lettuce, spinach and chives are the main crops.For greenhouse fruits, Korean farmers grow mostly citrus and grapes.Most of the greenhouses in Korea are plastic greenhouse facilities that were built more than 10 years ago.Plastic greenhouse facilities accounted for 99.2 percent of greenhouses in 2016, and are made of cheap vinyl.The area of glass-type greenhouse facilities has increased gradually to produce high quality vegetables such as paprika and tomatoes for the export market.As a result of high tech application and vertical farming, more high tech greenhouses will be built in the coming years. One of the sectors frequently mentioned in the policy on the Fourth Industrial Revolution in Korea is smart farming.In the “Five-Year Plan to Incorporate the Fourth Industrial Revolution” pronounced in 2017, smart farming is one of the major parts along with smart medical services, smart factories, and smart transportation.The Korean government plans to invest a total of two billion US dollars (USD) by 2022 for developing related technologies.

         Information and communications technology (ICT) convergence and artificial intelligence-based farming business for addressing climate change, bringing a paradigm shift in agricultural production, and creating new engines of growth.The Ministry of Agriculture, Food and Rural Affairs had announced that four smart farm innovation valleys (SFIVs) will be established by 2022.Sangju-si in Gyeongsangbuk-do and Gimje-si in Jeollabuk-do were chosen as the locations for the SFIVs.The SFIVs are agriculture clusters based on ICT to promote mutual growth of the agricultural industry including PFALs and related sectors by nurturing young talent and promoting technological innovation.The Korean government’s “Plan for Promotion of Agri-Food and ICT Convergence” has been implemented since 2013 for the purpose of applying ICT technologies to the production, distribution,and consumption of agricultural products.One of its major projects currently being implemented is the supply of “Smart Greenhouse Systems,” which supports the monitoring and control of plant cultivation environments via smartphones by providing high-tech sensing, monitoring, and control equipment to farms.Korea has developed various technologies for vegetable breeding, hydroponics, greenhouse structure, and hardware and software for controlling the environment in greenhouses, which can easily be diverted to vegetable production in PFALs.The term “plant factory with artificial lighting” (PFAL) refers to a plant production facility with a thermally insulated and nearly airtight warehouse-like structure.Multiple culture shelves with electric lamps on each shelf are vertically stacked inside.Other necessary equipment and devices for a PFAL are air conditioners, air circulation fans, CO2 and nutrient solution supply units, and an environmental control unit. Stacking more culture shelves vertically increases the efficiency of land use. Fluorescent lamps (FLs) have been mainly used in PFALs due to their compact size, but light-emitting diode (LED) lamps are now attracting great attention in industry and among researchers.

Data from USDA Report and Ministry of agriculture ,food and rural affairs