Tunnel farming for off-season vegetable cultivation in Nepal Source FAO Strategic Objective 5 – Resilience, in FAO Keywords Crop diversification, drought, vegetables, off season cultivation, protected cultivation, hail Country of first practice Nepal ID and publishing year 7714 and 2013 Sustainable Development Goals No poverty, zero hunger, climate action and life on land Summary This practice describes how to reduce better maintenance of the fertility of land, the impact of high and low temperature controlled temperature and humidity, fluctuations and hail storms that often protection from wild animals and insects and affect crop yields, as well as to grow crops better water conservation. off season to guarantee food supply at the In order to produce vegetables under household level to local farmers. protection, it is necessary to consider a wind-free area, but if this is not possible, Description windbreaks should be erected or planted. Vegetables are a required source of Water must not be very saline, as it is further vitamins, proteins, essential nutrients enriched by the addition of fertilizers. and carbohydrates for a balanced diet. In Finally, the tunnel must preferably be the mid-hill region in Nepal, farmers are situated close to a market, in order to limited to grow seasonal vegetables and facilitate that products reach the market are dependent on marketing mechanism of place as soon as possible. Crops such as demand and supply. cucumber, capsicum, tomato, pepper, bitter Growing off-season vegetables and fruits gourds, melons, brinjal and water melon means improving the diet and increasing the are highly valued vegetables that show household income. In the absence of storage significant increase in yield when grown in infrastructure and vegetable processing tunnel farming. industries, off-season vegetable farming is 1. Implementation of the technology the only viable option that can add value to the farmers’ produce. In general, tunnels may be: Temperature fluctuations during summer • Low: which are less expensive compared make the vegetable crop susceptible to to high tunnels but crop yield is low. insects, pests and diseases and similarly, cold Soil preparation, spraying and picking is temperature during winter create favourable difficult in this tunnel. Cucumber, melons, conditions for diseases. watermelons, bitter gourds, squashes, and snake The tunnels offer protection to vegetables gourds, etc. can be grown crops both in summer and in winter. The in these tunnels. TECA tunnel farming offers maximum crop yields, TECHNOLOGIES and PRACTICES for SMALL AGRICULTURAL 1/3 PRODUCERS Capacity Development

• Walk-in: which are lower in height must be considered while constructing compared to high tunnels. Walk-in-tunnels the structure. provide higher yields than low tunnels 1.2 Growing vegetables in tunnel farming because of better sun light and ventilation. The tunnel is suitable for growing Seeds are planted in plant blocks / tomatoes, cucumbers, sweet pepper and seed‑trays, and one seed is sown into each hot pepper. compartment of the tray, lightly covered • High: High tunnels give maximum yield and kept wet. Seedlings remain in the seed of crops and make easy soil preparation, tray until they have grown to about 10 cm. picking, spraying due to its width and Seedlings are then planted in the planting height. The tunnel is suitable for growing bags and kept wet. Climbers are trained up tomatoes, cucumbers and sweet peppers. to overhead wires by pieces of string. The 1.1 Building tunnel structures is bottom part of the string is placed in the inexpensive and relatively easy planting hole. The plant is placed on top of the string and firmed down into the growth • The structure of the tunnel is made of medium to remove air from the roots. Then bamboo sticks and wooden poles of the other end of the string is fastened to 1-inch diameter. the overhead wire. As single bamboo sticks are thin, combining two or three sticks bundled Tomatoes, cucumbers, green peppers, together provide a sufficiently strong bow beans and sweet melons can all be trained and girder construction, strong enough up in this way to the wires that are strung to hang strings that support vegetable above the rows and are fastened to the growth such as tomatoes, cucumbers and roof of the tunnel. The string is constantly beans. wound around the main stem of the plant. • A transparent plastic sheet is placed on This applies to all the plants except green the structure to allow sunlight during the peppers, in which case three or four stems day passes through the plastic sheet, and can be used. is absorbed by the black sheet spread 1.3 Irrigation in tunnels over the soil. This raises the temperature During summer, irrigation is required every to desired levels. five to seven days, depending on the type The plastic sheet on the soil serves three of soil, whereas in December and January, purposes: first it traps heat, second it light water is required every 10 to 15 days. reduces water loss and third it eliminates growth of weeds as seeds germinate from The quantity of water can be changed the holes made in the plastic sheet. keeping in mind the climatic conditions. In During winter and summer times, the water shortage areas, the most efficient roof may be covered with leaves or locally use of water are through drip irrigation, available crop residues to protect from maximizing the use of water, as well cold weather. During autumn and spring, as fertilizers, applied though drips as the structure is left without protection fertigation, especially in the initial growth facilitating aeration. stages. • Good cross ventilation and potential stresses caused by heavy wind, hail or rain

2/3 Figure 1. High tunnel • Provides opportunities for crop diversification. • Household income for women. • Less labour requirement. 3. Minimum requirements for the successful implementation of the practice • Access to capital. • Availability of local materials for © FAO/TECA construction. • Protection from heavy wind. 4. Agro-ecological zones Figure 2. Low tunnel • Subtropics, warm/mod cool 5. Objectives fulfiiled by the project 5.1 Women-friendly Provides household income to women. 5.2 Resource use efficiency More efficient use of land in building the tunnels enables improved protection from © FAO/TECA extreme climate. Less labour required which means improved use of resources. 5.3 Pro-poor technology 2. Technical, economic, financial, social and Practice allows for more crop diversification environmental attributes of the technology and cultivation throughout the year which • Protection from heat and cold waves and guarantees more food security and more hail storm. added source of income. • Reduces the impact of vegetable crops. • Possible to cultivate the crop throughout the year.

TECA TECHNOLOGIES and PRACTICES for SMALL 3/3 AGRICULTURAL PRODUCERS