It's like being in the Mercedes Benz of greenhouses. That is the first impression left by the Colombia-Netherlands Horticultural Center, a demonstration and research space for Colombian agriculture and floriculture equipped with the latest technology in automation and fertigation monitoring for crops, temperature and humidity measurement, as well as in the opening of windows and shutters of the greenhouse, according to the climatic conditions of the environment (solar radiation and rains). All of this improves the production of crops, such as tomato, the first plantations which will be produced there, by up to five times: "Technology and management can help us extend the useful life of a plant much more than through traditional agriculture. This means we'll achieve producing more without renewing the crop," stated Carlos Bojaca, who led this project from the Jorge Tadeo University.
The space, which was completed in May at the Alberto Lozano Simonelli Bio-Systems Center, has an area of approximately 200 square meters, distributed in two independent compartments that can accommodate up to 216 plants each. The Horticultural Center required a total investment of nearly 100,000 euro (about 340 million pesos). It was financed under the framework of the "Center for Training and Knowledge Colombia" (CeCaCoCo), a cooperation program of the Government of the Netherlands, which includes the participation of the Jorge Tadeo University (Utadeo), Saenz Fety, and Horti Fresco.
The delegation of the Embassy of the Netherlands in Colombia and the Head Master of the Jorge Tadeo University, Cecilia Maria Velez, will inaugurate this greenhouse on June 21. In its first phase, the space will be used to train about 300 tomato growers from Boyaca and Cundinamarca, and, according to expectations, farmers and flower growers from all over the country will use this space as of 2019.
We'd like you to tour this greenhouse via this report a few days prior to its inauguration.
The brain behind the operation of the Horticultural Center lies in its control room, located in a container on the outskirts of the greenhouse. Inside, it houses two systems. One system is in charge of controlling its climate, that is to say, regulating the temperature and humidity of the greenhouse. The other system controls the correct nutrition of each plant, through fertigation (water and fertilizer).
Both systems are computer-driven, thanks to specialized software that sets the climate and nutrition management conditions. The software also monitors the behavior of the greenhouse, measuring variables, such as pH, humidity and temperature, through sensors in the crops and a meteorological station, which is located in the upper part, at one end, of the control room. These data will allow the agronomy specialist or crop technician to implement strategies for the application of fertigation, and temperature control. Additionally, the greenhouse's control system can be remotely monitored and managed.
This control system also has a panel that activates or deactivates the internal engines of the greenhouse, which allow the opening and closing of the windows and shutters of the place. This subsystem works automatically or manually and connects directly to the computer.
Finally, the peripheral brain of the computer, a giant processor in charge of receiving and centralizing the signals coming from the greenhouse (sensors and weather station) and sending the orders registered in the computer, is part of this first system.
The greenhouse's fertigation system is the most modern system of this type in the country. In fact, to date, only five greenhouses in Colombia handle a similar system, consisting of tanks containing concentrated nutrient solution, a substance necessary for the growth of plants. When the system is activated, it takes filtered and treated water from the supply tank of the Bio-Systems Center and mixes it with the programmed amounts of fertilizer. This mixture takes place in the fertigation machine, consisting of a series of pipes and valves, as well as sensors that measure the PH and electrical conductivity to determine if the mixed nutrient solution is correct, as the plants in a hydroponic substrate are very sensitive to nutritional changes.
The greenhouse's supply tank, which as a capacity of nearly 13,800 liters, is located behind the control room. Near it, there is a weather station that records temperature, solar radiation, rain, wind speed and direction.
The greenhouse has a metal structure and it's divided into two compartments that allow managing different climates and nutrition settings, to carry out comparative studies on productivity. Inside them, there are seven rows of plants, each one suited with a support system where the plants are planted in a coconut fiber organic substrate, without nutrients. The supports have channels to discard the excess fertigation in plants. This substance is currently being discarded but, according to Bojaca, the idea is t reuse it in the future through a process of disinfection and treatment, just like the Netherlands does.
The culture has two sensors to regulate the temperature of the greenhouse. One of them measures the temperature of the air and the other one performs a mathematical calculation to determine the relative humidity. This information is then sent to the control room to decide in which direction the roof and windows should be opened. Thus, when solar radiation exceeds the programmed temperature limits, the roof windows of the greenhouse open, and when it rains, they close. The radiation is being used as an irrigation strategy; when it accumulates in the crop, the order is to water the plants.
Fertigation reaches each of the plants through a dropper, which delivers the water with the programmed fertilizer solution. However, to ensure that they receive the necessary mixture, the technicians conduct a direct control measure, which consists of an independent dripper for the calculation of actual and drained irrigation. This is the only type of monitoring that is performed manually.
In order to stabilize the plants and direct them in their growth, which can take eight to ten months, the researchers work with a system of thin ropes the plants coil on. This allows the fiber to fall as the plant grows, providing them with space and directing the stems to the supports.
On the roof there are two motors that control the opening and closing of the windows, which are made of a plastic that is thicker than the one traditionally used, thus guaranteeing its durability and greater heat capture.
There's also another engine that controls the screens or fabrics that regulate the radiation throughout the day, extending them so that the greenhouse does not heat up. Finally, there is an engine that controls the side blinds of the greenhouse, which are made of aluminum fiber and that work as a blanket, as they are lowered to conserve the temperature during the night: "the climates in the Sabana de Bogota is not suitable for growing tomatoes. The Horticultural Center would allow maintaining the temperature stable throughout the day and night. Currently, producers grow tomatoes in the area, but the yields are low and producing them takes a long time," said Bojaca.
In order to obtain quality water for the plants, the reservoir of the Bio-Systems Center underwent general maintenance for three months, and it is now in optimal conditions. During that time, the membrane was changed and the mud was removed from the bottom of this water tank. A new geo membrane and purification filters, which retain physical, chemical and microbiological particles were also installed. This water, originally from La Mana, passes through some tanks where it is filtered. Then it is sent to the reservoir, and from there, to all the greenhouses of the Bio-Systems Center. Before and after of the water reservoir of the Alberto Lozano Simonelli Bio-Systems Center (Slide the arrow to see the change)
Part of the research to be developed in the Horticultural Center focuses on integrated pest management, systems that combine biological, chemical, and plant extracts. The greenhouse also has a trap which expels sexual pheromones that attract males and females of the Tuta absoluta pest (tomato moth), trapping them on a membrane composed of glue. These techniques are known as ethological control.
Finally, the Horticultural Center will have a disinfection area at its entrance to prevent the entry or transfer of any pathogen or plague that may affect the crops in this space: "This serves as a model for farmers to apply, because many times these organisms can be transferred through the body, clothes or hair these," stated Luz Stella Fuentes, the director of the Bio-Systems Center Alberto Lozano Simonelli. The area would have protection elements, such as disposable gowns, caps, masks and leggings, as well as a nebulizer center with special water, sinks, and disinfectant powder for the feet.
Source: Emanuel Enciso Camacho, Communication Office of the Jorge Tadeo University