Low Cost Greenhouse Technology for Vegetable Production in Nigeria

Low Cost Greenhouse Technology for Vegetable Production in Nigeria

A greenhouse is a structure with walls and roof made chiefly of transparent material, such as glass or plastic materials in which plants requiring regulated climatic conditions are grown. These structures range in size from small sheds to industrial-sized buildings. The interior of a greenhouse exposed to sunlight becomes significantly warmer than the external ambient temperature, protecting its contents in cold weather. The technique of using greenhouse to make crop production under regulated environmental condition is generally called greenhouse technology. Many commercial glass greenhouses have production facilities for vegetables or flowers. The transparent greenhouses are filled with equipment including screening installations, heating, cooling, lighting, and may be controlled by a computer to optimize conditions for plant growth. Greenhouse are heated up because of the incoming solar radiation which warms plants and soil inside the building faster as there is no heat transfer by convection.  The air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall.

Conventionally, greenhouses are equipped with screening installations, heating, cooling, and lighting and may automatically be controlled by a computer system.  The transparent materials used for a greenhouse act as a barrier to air flow and is used for trapping energy, warming the air near the ground and preventing it from rising and flowing away.  Glasshouses are used for growing some crops throughout the year such as lettuce and other vegetables.  Crops are protected against adverse climatic conditions such as wind, cold, dust storms and blizzards, precipitation, excessive radiation, extreme temperatures, insects and diseases.  Light and temperature control allows glasshouses to turn in arable land into cultible land and can be useful for crops production where such crops cannot survive the environmental condition especially in the harsh deserts.  The closed environment of a glasshouse has its own unique requirements, compared with outdoor production, pests and disease infestations and extremes of heat and humidity, are also controlled. Glasshouses are often used for growing vegetables, fruits and flowers. Also, glasshouse production require relatively small amount of area compared with field-grown produce and, the return on investment can be good if the requisite markets can be found. Glasshouse-grown vegetables cannot compete with comparable field-grown crops based on price; therefore, Glasshouse-grown vegetables often are marketed to buyers based on superior quality and off- season availability.

Greenhouse offers golden opportunity to farmers for crops growing  anytime  of the year and make the most use of land. The  greenhouse technology provides plants exactly what they need – a perfect climate, a right amount of sunlight, nutrition, exact amounts of water, carbon dioxide for photosynthesis,  proper ventilation and hostility to pests and diseases. The other benefits are that crops of good quality and higher yield can be grown, water requirement is lower compared to crops grown in open space, while the low labour-intensive method helps in controlling pests and diseases. Farmers can achieve 8 - 10 times yield of crops as compared to the open crop cultivation.

Greenhouse technology, if properly explore, has the potential of at least reducing the deficit in the country’s demand significantly. For instance, a 2013 report from the Central Bank of Nigeria indicated that about N16 billion was spent annually on the importation of tomato paste into the country. The report further revealed that the demand for tomato in Nigeria was estimated at 2.3 million metric tons per annum, while the output was 1.8 million metric tons out of which about 50 percent  was being lost due to lack of good storage facilities and poor developed marketing channels. This implies that 900,000 metric tons was the actual output per annum and that about 1.4 million metric tons is required annually to cover the deficit in the demand. Nigeria is the 13th larger consumer of tomatoes in the world and Nigeria should grow tomatoes to meet the demand of the citizens. This is possible with greenhouse technology, Nigeria can stop importation of tomato especially now that the Dangote tomato processing plant is about taking up at Gafan Tomato market in Kano state.

In Nigeria, the use of greenhouses has been confined to research institutes and tertiary institutions where they are often used for on-going research. Private ownership of greenhouses is not too popular until recent years when Dizengoff West Africa Nigeria, a member of the United Kingdom Balton CP Group and few of the organizations have introduced greenhouse farming system into the Nigerian market. Although, past and present crops of Nigerian leadership  have repeatedly restated  Government commitment to the food security programmes. They have not been able to harness greenhouse farming as one of the many options that have been used elsewhere which could possibly be introduced in the Nigerian environment. As such, greenhouse farming is grossly underutilized/popularized and there is need for government to invest more in this agricultural sector. This will certainly make Nigeria a self sufficient nation in the area of food production especially in areas like Vom in Plateau State. Plateau has been identified as a place where many exotic plants such as Passion fruit, Irish potatoes, Cabbage, Roses, other ornamentals, Turnip and Strawberries can be grown because of the temperate nature of the Jos - plateau climate. However, greenhouse technology can be adopted in every part of Nigeria both in urban and rural areas, which will certainly make the country one of the leading nation in terms of food production.

Greenhouse technology is handy for increase productivity and poverty alleviation but not accessible to many Nigerians because of prohibitive cost. This prohibitive cost of construction and maintenance of the convectional greenhouse is one of the major reasons why many people became aloof to the technology. This is because majority of Nigerian farmers are peasant farmers cannot venture into the business of greenhouse farming without support from government in form of grants and/or subsidy. For instance, the cost of materials and installation of a conventional greenhouse of 24 by 8 square meters, which can contain 480 stands of tomato cost between N1.4 to 1.8 million. Obviously, this astronomical cost makes it discouraging to most Nigerians thereby making the technology unpopular. This teething problem associated with conventional greenhouse made Researchers in National Agricultural Extension Research and Liaison Services (NAERLS), one of the research centres of Ahmadu Bello University, Zaria to source for locally made materials to construct the greenhouse.   The feat was achieved and a greenhouse was constructed. Although, not all the materials were locally available but the significant percentage of the materials were locally sourced.  The cost implications of the locally made greenhouse is half the price of the conventional/imported materials of the standard greenhouse. The locally made greenhouse is 30 by 12 m², which can contain 1,056 stands of tomatoes.  The essential materials required for the locally made greenhouse are polyethylene 200 micron 10 meters by 42 meters at average cost of N330,000, insect netting at average cost of N485 per square kilometer, planting bags, trays, organic fertilizer and a set of drip irrigation kits with filter for 16 by 30 m2 greenhouse at average cost of N78,000. The most expensive components of the greenhouse are the polyethylene and drip irrigation kits.  the polyethylene is the transparent material use for covering the greenhouse structure. This material can withstand both mechanical and thermal stresses caused by sunlight and other harsh weather conditions. For now, there is no apparent alternative to this important material. However, alternative is being sought for drip irrigation kits. Already, various perforated sizes of PVC pipes are being tested to serve as lateral line for the drip irrigation system.

Greenhouse technology for vegetable production has bright prospect as a tool for increase food security and income generation to many farmers. This is because vegetables are being produced in all parts of Nigeria. Example in North west and North east; Onion, Tomato and Pepper Tomato, Onion, Pepper Okra, Egg-plant, Amaranthus, Roselle, Pumpkin, Water-melon Carrot, Lettuce are Cabbage being produced.  in North Central;  Pepper, Onion, Tomato, Okra, Amaranthus, Egusi- Melon, Cucumber, Water- Melon, Garlic are Ginger can be produced using the greenhouse technology. In South West, Vegetable crops being produced are  Tomato, Pepper, Okra,  Melon, Amaranthus, Celosia, Corchorus and Egg- plant while in the South East, the crops are Egusi-melon, Okra Amaranthus, Gnetum, Water leaf, Vernonia,  Egg- Plant and Pepper.

In conclusion, the development of low cost greenhouse technology has offered opportunity to the majority of the Nigerian  farming population to enhance their productivity for food security and income generation. Fortunately, NAERLS is ready to partner with relevant agencies to train farmers on the acquisition and management of greenhouse technology. Governments at local, state and federal levels should extend their support to this improved method of crop production. This is way Nigeria may be on path to progress and prosperity.

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