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Establishing block and polybag mini nurseries in drought prone areas of NW-Bangladesh
Most farmers in Bangladesh depend on subsistence farming with extremely small land holdings. Great parts of Bangladesh are flooded every year; to large extent agriculture systems have been adapted to this normal flooding. However, besides normal peak floods in July and August and late floods extending in September, early floods from May to June have negative impacts on food crop production potentials. As the country is already deficient in food, large damages of food crops due to floods and droughts may endanger food availability and local stability of supply. Crop diversification is advocated at the policy level to ensure food, nutritional and environment security. Farmers are interested in alternative small scale economical activities such as seedling/sapling production which contribute to livelihood diversification and help overcome difficult periods in case the main crops were damaged by natural hazards. The area where the nurseries were established and tested was in the mixed rainfed farming systems in North West Bangladesh in the agro ecological zone of warm humid tropics.
The objective of nursery establishment in NW Bangladesh was to produce drought tolerant plant and tree seedlings/saplings and to earn additional income from alternative enterprises. The presence of a nursery also encourages people in the community to plant trees and ultimately contribute to reforestation.
Implementation of the Technology
Two types of nurseries are recommended for farmers with small land holdings: (i) block nursery and (ii) polybag nursery. These nurseries are most suitable for kharif-I season (March to May), especially in the Barind areas (Gomostapur, Porsha and Sapahar upazillas).
(i) Design and set up of block type nursery
The total area of a block mini nursery should be 400 m². Its design requires nursery blocks, beds, and irrigation and drainage canals. The blocks consist of seedling raising blocks, soil preparation and potting blocks, compost block, working shed, and seed germination block. A 90 cm pathway is required between two blocks. On both sides of the pathway there should be a ca 20 x 30 cm wide/deep drainage canal for the rapid outflow of excess water during monsoon. Blocks are further subdivided into 10-12 beds, according to the size and objectives of the nursery owner. There need to be seedling/sapling beds, seed germination beds and beds for younger seedling/saplings. The beds will be arranged in east-west direction to ensure equal distribution of sunlight. Each bed will be 1 m in breadth and 3-4 m or more in length. There must be 45 cm wide pathways between the beds. Between those small canals of 15-20 cm depth are recommended to facilitate the drainage of water during monsoon. A small space in a corner of the area needs to be set aside for the construction of a nursery shed. Some space on the other corners needs to be set aside for compost pits, potting and bagging, as well as for management practices.
The entry road to the nursery should be spacious enough for transportation of products by vehicles.
Preparation of germination bed:
The ideal germination bed size is 4 ft X 10 ft. The following steps are required for its preparation:
- Dig soil 25-30cm deep and pulverize thoroughly, break lumps of earth and remove remaining roots and rhizomes. Allow the soil to dry in the sun for 2-3 days for sterilization, to help prevent damping off.
- Add 8-10 baskets (a medium size bamboo basket is commonly used by villagers) of sand and 2-3 baskets of well decomposed compost. Mix thoroughly and raise the bed.
- Level the bed with a stick and leave to rest for a few days.
- Water the bed thoroughly 6-12 hours before sowing seeds.
Preparation of seedling bed for transplanting:
- Cultivate the land by spade, break lumps of earth and remove all debris. Leave to dry for 2-3 days.
- Spread 15-20 baskets of good compost for every 120cm x 600cm bed, and mix well so the soil becomes loose and soft.
- Raise the bed by 7-10 cm to facilitate drainage. Level the bed with a stick and expose to sunlight for 2-3 days for sterilization.
- Water the bed thoroughly 6-12 hours before planting.
(ii) Polybag nursery
To raise polybag seedlings, nutrient rich soil is required. Generally soil with more organic carbon content is highly suitable for the preparation of polybag nurseries. In polybag and seedling beds, sand is required to make the soil lighter and loose, facilitating easy germination and root penetration. Fine and dry sand may be collected from river beds and mixed with soil before filling the polybags. If soil is clayey then it is necessary to add sand, but if the soil is already sandy then addition of sand is not required. As the seedlings grow on a limited area of seedling bed and polybag, they consume nutrients from the soil. The soil of the seedling bed and polybag must therefore be provided with additional nutrients by adding organic matter. Compost, which is a rich source of organic matter, will have to be added to the soil. So compost will have to be prepared regularly in the nursery site.
Size of polybag - Choose according to species characteristics and length of time that the seedling will be in the bed. For timber, leguminous species and smaller fruit species like citrus, guava and papaya, 10cm X 15cm polybags are ideal. For seedlings that need to be kept for longer periods and for larger fruit seedlings like mango and jackfruit, 15cm X 25cm are required.
Filling polybags with soil -
- Make 4 to 6 drainage holes in the polybag using punch machine, pointed iron rod, pencil or stick.
- Thoroughly mix 3 parts of soil with 1 part of compost and 1 part of sand (according to the texture of the soil being used).
- Sieve the soil mixture, loosen it and remove debris, hard particles and lumps.
- Fill the polybag up to the brim with the prepared soil and pack firmly enough to stand. Do not over-compact.
Bed preparation for polybag - Level the land with spade and prepare beds 120 cm x 600 cm in size. Set frames around the bed to keep the polybags in an upright position. Frames may be made from locally available materials like bamboo, bricks and poles.
References and Further Reading:
Livelihood Adaptation to Climate Change (LACC) – DP9/1-BGD/01/004/01/99, Asian Preparedness Centre, Food and Agriculture Organization of the United Nations, Rome, 2006 – Technical guideline on the establishment of demonstrations during kharif I season
Ministry of Agriculture of Bangladesh – Department of Agricultural Extension, http://www.moa.gov.bd/
Bangladesh Agricultural Research Institute (
Bangladesh Rice Research Institute (BRRI), http://www.brribd.org/about_us/index.htm
Fecha de creación
The Natural Resources Management and Environment Department provides leadership, technical and policy advice and knowledge towards the sustainable use of the earth’s natural resources (land, water, genetic resources and biodiversity). The Impact, Adaptation and Environmental Sustainability team of the Climate, Energy and Tenure Division (NRC) develops the knowledge base on the impact of climate, climate change and climate variability on agriculture, and facilitates the use of this information and knowledge through field projects. The team also supports capacity development at national level by supporting governments to integrate disaster risk reduction in the agriculture sector as well as identifying, testing and validating in cooperation with various partners climate change adaptation and disaster risk reduction good practice options to build resilience of all actors in agriculture to the impact of climate change and extreme weather events.