How many ways are there to grow a head of lettuce? Besides growing the traditional way in an open field, you can grow lettuce and other vegetables in various soilless, protected systems. Protective structures include high tunnels, greenhouses, shade structures, or even warehouses or shipping containers with LED lights. Vegetables can be grown in soilless media, hydroponic or aeroponic systems, and of course in native soil. Production systems include vertical towers or racks, floating rafts, shallow gutters (NFT), buckets, bags, and trenches. These systems can be low tech or high tech with sensors, climate controls, artificial lighting, and automation. Growing in protected systems is also called controlled environment agriculture (CEA).
Expansion of CEA vegetable production
CEA systems appear to be on the rise. Although data from the 2017 Census of Agriculture are not available yet, the 2012 Census showed a 5-year 59% increase in the area of vegetables and herbs grown under glass or other protection (USDA). Recent news reports suggest that the expansion of protected vegetable production continues. Last year, Wendy’s announced that it will source tomatoes that are greenhouse-grown only (The Packer).
Why is CEA becoming more common?
Protected agricultural production offers several advantages, but also challenges. CEA systems achieve higher yields per acre than open field production. In areas with high land values, it can become economical to substitute capital and energy for land. In other words, CEA systems use less land but have higher expenses for structures, heating and cooling systems, and electricity or fuel. Controlling the environment allows the harvest season to be extended, in some cases going year-round. CEA systems also have the potential to reduce weather-related risks, decrease water use, and reduce the need for pesticides. Wendy’s cited consistency of supply, quality, and freshness as reasons for switching to greenhouse-grown tomatoes (The Packer). Still, growers may find it challenging to grow vegetables in these systems and keep costs below the value of production.
UF/IFAS Extension programs on hydroponic vegetable production
The University of Florida, IFAS Extension, offers several programs on protected and hydroponic vegetable production. Four programs are offered this spring at the UF/IFAS NFREC-Suwannee Valley in Live Oak: Starting a Successful Hydroponic Business (March 15-16), Hydroponics Short Course for Teachers (March 29), Hydroponic Gardening for the Homeowner (April 10), and Greenhouse Economics: Costing & Profitability for Hydroponic Vegetable Production (April 11). You can register online by clicking the course links above.