The development of hydroponics vegetable production at Val d’Andorre farm |01 September 2017

The Val d’Andorre farm is in the process of initiating the use of hydroponic methods as a means of growing its plants. Hydroponics is essentially the art of growing plants without soil and the word itself comes from Greek words meaning ‘working water’. It is a subset of hydroculture where the plants grow in an aquatic based environment that has all the mineral nutrients needed as their feed. This method has been around since the Middle Ages but not until the 20th century did scientists perfect this technique to make it more efficient. With production dates set for early 2018, a representative of the Val d’Andorre farm gives a detailed insight into this relatively new technology and its benefits.

Q: What were the main reasons for initiating hydroponic vegetable production?

A: Today, Seychelles is not able to contribute significantly to the demand of fruits/vegetables/aromatic plants of hotels and restaurants, despite the dependence on tourism for revenue. Around 80% of the food consumed in Seychelles is currently imported from distant markets and at high costs (The Seychelles and FAO, 2015). Hence, ISPC Seychelles Ltd is developing a hydroponic vegetable system at Val d’Andorre for the following purposes: obtain equal/superior quality of commodities in comparison with imported products; obtain sufficient/regular production of produce; help Seychelles become autonomous in the production of vegetables/aromatic plants; help to satisfy demand; reduce importation costs and reduce the ecological impacts of importation.

Q: What are the advantages of such a system?

A: The main advantages of the soilless versus soil culture are the increase of yield and quality. In soil culture, the yield is limited by the availability of nutrients and light. In soilless crops, these limits do not exist and the number of plants per metre square can dramatically increase. The quality of harvest products is higher and more constant. In opposite, depletion in K (potassium) and/or Ca (calcium) can happen in soil culture. Consequently, fruit disorders can appear and the storage of commodities can be shorter. With hydroponics, it is possible to produce more vegetables of better quality on a small surface. As it is soilless production, the quality of the soil, physical and biological, is not important and the production can be done nearly everywhere.

The rotation of different crops would not be necessary and watering/nutrition are controlled. This leads to substantial economy of water and fertilisers, allowing close monitoring of plant nutrition and adaptation to the needs of the crops, subsequently leading to improved quality.

Due to the equatorial climate, there are a lot of insects and viruses in the Seychelles environment affecting non-protected crops very seriously and obliging farmers to use a lot of costly and sometimes dangerous pesticides. Even natural, clear water from a source in the hills needs to be treated as it contains natural viruses harmless for men but harmful for crops. However, the direct irrigation with the hydroponics system restricts the development of weeds which can be a haven for pests and also limits weeding. The use of pesticides can be limited to the minimum as a lot of pests and diseases are kept away from the plants. Furthermore, there is no use of herbicides as no weed can develop in the system.

Q: How does such a system benefit farm owners/workers as well as the local population?

A: One of the advantages for Seychellois farmers is better work conditions. Indeed, the work is less physical and the less use of pesticides decreases contact time with pesticides. The production, which is more controlled, is also more constant over the year, allowing economic safety for the farmers.

For the Seychellois people, this local production of vegetables allows them to have access to healthy and varied food at a reasonable price. The farm sells its products to whoever wants to buy so the produce is available to everyone. The aromatic herbs will be very affordable compared to what there is on the market today in the local supermarkets.

Q: What type of crops will be grown?

A: The selected varieties are European, including aromatic plants, tomatoes, pepper, cucumber, zucchini, sweet melon and lettuce.

Q: Was any research conducted prior to the project starting?

A: Yes. A market demand approach was used, measuring the needs and prices of vegetables on the Seychelles market, retail or wholesale to the tourism industry. Then we conducted a detailed scientific analysis of the Seychelles environment. We have worked with agronomist engineers and a professor from a Belgian University. The study has allowed us to define the necessary equipment (e.g. the type of greenhouse to the model of hydroponic tables and water treatment system) and cropping techniques that one has to invest in and develop in order to successfully crop vegetables such as tomatoes, peppers, cucumbers and aromatic herbs.

The high investment into the necessary equipment seems to be compensated by the costs of airfreight that one needs to pay to import the same vegetables and that substantially impacts the selling prices of the imported products.

Q: What techniques are employed to meet production targets?

A: Considering the equatorial climate, several techniques were studied and the recommendations are:

-           Growth under shelter: protection of the plants from heavy rainfall and insects.

-           Soilless cultivation or hydroponic culture will give the following advantages: removal of soil constraints (mineral deficiencies, inadequate physical structure, pathogens); precise control of water and mineral nutrition; control of a substrate disinfection facility (good control of soil borne pathogens); higher yield potential per surface unit.

We chose greenhouses instead of tunnels because they are more solid and can resist to climatic conditions. Furthermore, management of climate is easier in greenhouses as we can open the roof. All the openings will be protected by an anti-insect net.

There will be completely integrated control systems, combining climate and watering. The process computer program will control the climate and irrigation requirements inside the greenhouse. That will create the ideal growing climate at every moment of the day, perfectly adapted to the plants’ needs. The computer adjusts any technical process to control conditions to the current situation in the greenhouse.

The water of the drip-irrigation will be collected and reused after a UVc treatment. The goal is to minimise water consumption by avoiding the development of diseases transmitted by water.

For all the crops, we will use pathogen-free substrate: rock-wool support for the tomatoes, sweet peppers, cucumbers, zucchini and melons; and peat-lite mix for the herbs and aromatics.

Q: You mentioned that you have worked with a professor from a Belgian University for this development. Tell us more about his/her background and their role in this project.

A: Professor Haissam Jijakli and his team from Gembloux Agro-Bio Tech (University of Liège – Belgium) supervise the project. As a professor in plant pathology, he was working during the last 25 years in the development of methods to control plant pathogens for temperate and tropical crops. He is specialised in integrated production combining chemical pesticides with methods based on (micro)-organisms and their derivatives to protect plants against phytopathogens. The professor has participated in or coordinated more than 30 projects with Belgian/foreign partners and has produced more than 400 scientific publications. Thanks to these results and fruitful collaborations, his laboratory has acquired an international recognition in integrated production and biocontrol using fundamental and practical approaches. His concern is to create a strong link between the academic and industrial worlds in order to implement agricultural techniques which are economically, environmentally and socially affordable for the agricultural sector. Gembloux Agro-Bio Tech is the oldest educational and research institution in Belgium (1860) which is exclusively dedicated to agronomic sciences/biological engineering and has a lot of experience in agriculture in tropical countries since its creation, particularly in Africa.

Q: Will the products be organic?

A: Thanks to the equipment, we will be able to reduce the use of chemicals to practically nothing. Growing vegetables in a controlled and protected environment such as sealed sophisticated greenhouses and on hydroponic tables allows minimum use of pesticides and other eventually needed chemicals to keep away the bugs and viruses.

Q: What are the challenges associated with this venture?

A: The main problems are: difficulty of cultivation in an equatorial climate and ground conditions while achieving consistent production over time; high temperatures (24°C-31°C) and humidity (70-80%) that can be negative factors for production in terms of yield and quality. On the other hand, the stability of weather conditions (mainly temperature) during the year allows us to grow vegetables all year round.

Q: When will you begin production?

A: We are now in the phase of ordering all the chosen equipment. The greenhouse will be arriving in Seychelles at the end of November. The farm land is 6 hectares and we will install 6,000 m² of greenhouses; the rest of the land will be planted with lime trees, avocado trees and coconut trees. We will also grow melons and watermelons outside the greenhouses. We will maintain a small production of dragon fruits which was started before our project but revealed to be not profitable due to the high costs and low demand.

We encountered a slight delay in the delivery of the water plant system which will arrive in Seychelles in January 2018. We hope to be able to start producing during the course of the month of March. We will assure weekly production of all the vegetables grown in the greenhouses on hydroponic tables.

Plants are grown under shelter which protects them from heavy rainfall and insects

Photos: Photo credit: Val d’Andorre Farm