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Helping homestead gardeners mitigate the impact of soil salinity

By Erica Roy Khetran

Erica Roy Khetran is the Country Director for Helen Keller International (HKI) in Bangladesh. She has lived and worked in Asia since 2004 with a focus on emergency, food security and nutrition programmes.

The soil salinity survey was led by Project Laser Beam team members, Md. Hafizur Rahman and Moshfikur Rahman-Sr. Thanks to Md. Amun Uddin for his extensive inputs into this article (including photos) and leadership in assisting homestead gardeners in Shymnagar.

Homestead food production (HFP) is an effective way to help poor families increase access to nutritious food and new sources of income. HFP enables women to access fresh vegetables for themselves and their children directly, instead of relying on a male family member to purchase them. Furthermore, proceeds from household gardens are usually controlled by women and thus more likely to be used for education, healthcare and other activities, which directly benefit women and children. Helen Keller International (HKI) has implemented HFP programmes throughout Bangladesh since the early 1990s. As part of the global Project Laser Beam initiative, the Kraft Foods Foundation is currently supporting HKI to increase women’s asset base and food security through HFP, improve nutrition, address gender barriers and intra-household communication and strengthen farming groups.

Improved compost pile

However, a changing climate requires that new practices be integrated into strategies to promote HFP, particularly in the vulnerable areas of southern Bangladesh that face frequent floods and cyclones. Shymnagar, a sub-district in south-western Bangladesh bordering the Bay of Bengal, is particularly vulnerable to floods and storms. The impact of these events on food production can persist for years. In May 2009, the area was hit by tropical cyclone Aila, a category 1 storm. Heavy rain and wind led to a tidal surge of up to 10 feet and several rivers broke through embankments (already weakened by nearby shrimp farms which cut holes through the embankments to flood their ponds), causing widespread inland flooding. In some areas, 2-3 feet of water remained for up to 20 days. In addition to immediate destruction of homes, crops and assets and widespread displacement, the waterlogging damaged fruit and timber trees and resulted in increased soil salinity which, three years later, continues to inhibit agricultural production.

The soil salinity is worst during dry periods. The spring of 2012 was particularly dry, with no rainfall during the month of May, according to the local farmers and the Department of Agricultural Extension. With support from the Kraft Foods Foundation, HKI surveyed the impact of soil salinity on household gardeners in Shymnagar during this period and rolled out strategies to help families continue vegetable production.

Soil salinity in formerly flood affected areas

A survey, including visits to 144 gardens and three focus group discussions, was conducted in late May, 2012, by HKI’s Project Laser Beam staff. The purpose of the survey was to assess the impact of soil salinity on vegetable cultivation in Shymnagar, identify the most tolerant varieties of vegetables, document local practices to cope with salinity and, ultimately, develop recommendations to assist families in areas with high salinity with continuing vegetable cultivation. All households had previously been provided with eight varieties of summer vegetable seeds and HFP training by Project Laser Beam.

Of the surveyed household gardens, levels of soil salinity were very high in 38% of gardens and moderate in another 34%. A total of 14% of gardens were completely destroyed by soil salinity, meaning that no seeds could successfully germinate. In the most saline areas, farmers and the local Department of Agricultural Extension report that, following cyclone Aila, standing flood waters persisted for 15-20 days. In moderately saline areas, flood waters stood for seven days or less. No gardens were found to be completely without soil salinity. In the most affected areas, household ponds, the primary source of irrigation, were also extremely saline and thus unsuitable for irrigation.

Fully damaged garden, with the garden's owner

About half of households were already implementing practices to cope with soil salinity. Among these, 38% were using organic compost and 34% were planting crops in pits which were first leached with water. However, households with the knowledge and means to adopt these practices tended to be among the better off; poor households who are more reliant on their gardens for food and income had fewer coping mechanisms and were thus most affected by the salinity.

It is worth noting that the increased soil salinity since cyclone Aila has affected other aspects of the food production system in Shymnagar. Small farmers report that production of rice, an important cash crop and source of food, has decreased since the storm. Households with access to larger plots of land have moved from rice cultivation to shrimp cultivation, which provides fewer day-labour opportunities for poor households.

Mitigating impact of soil salinity on home gardens

Based on survey findings, HKI promoted several practices to help families whose lands were very affected by salinity, continue HFP. This strategy focused on practices that required minimal or no financial investment, recognized the limited availability of fresh water to irrigate and flush the soil, and could be implemented primarily by women.

Partially damaged garden

Key practices included mulching with rice straw, coconut coir or other locally available organic materials to increase water retention of the soil. Households were able to obtain these materials free of cost, in most cases from their own family farms. Development of compost pits near homestead gardens and use of compost in preparing and managing the soil was also encouraged. Compost effectively increases organic content and available nutrients in the soil, helping to counteract the effects of salinity. Composting is free of cost, but requires an ongoing investment of time and space on the part of families. Lime, purchased by households from the open market, was also used to treat saline soil. The cost of lime was minimal and easily managed by households. However, given cultural limitations on access to markets, women frequently needed to request that a male family member purchase the lime.

Leaching requires covering the area with sufficient water to fully infiltrate the soil and stand on the surface before being drained away. This is effective, but for families with limited access to fresh water leaching is impractical for large areas. HKI encouraged two practices that enabled households to increase production by leaching much smaller areas. First, sowing of seeds in beds, with the soil first leached of salt and then prepared with mulch and compost. Families then transplant seedlings to larger fields after heavy rain, when the soil is less saline. Secondly, HKI promoted ‘pit cropping’, in which households sowed crops in small pits which were first leached and prepared with compost. This was most effective when combined with other practices, including seed beds and use of mulch and lime.

Finally, HKI’s survey found significantly greater resilience in salinity among some vegetable crops. These include Indian spinach, sweet gourd, okra and Kangkong- a leafy green vegetable rich in vitamins A and C as well as iron and calcium. In most cases, promotion of these vegetables required distribution of seeds directly to households. This is particularly true for Kangkong, which was among the most saline-resistant crops but is relatively new to southern Bangladesh. Thus this strategy, while highly effective, may not be practical in programmes which do not have resources for agricultural inputs.

Village model farmer demonstrates adding compost to pumpkins planted in pit crop system

Container gardening

In areas most affected by soil salinity, even leaching and measures to increase soil water retention and nutrient content will not enable households to grow vegetable throughout the year, or will only enable gardeners to produce a limited number of crops (mainly kankong and Indian spinach) in the dry season. Container gardening is an effective strategy to increase the number of planting seasons and garden diversity in these areas, though ongoing training and technical support is required to introduce this new practice.

Containers available to households in Bangladesh at low- or no-cost include nylon bags (such as those used for animal feed), jute shopping bags, old metal and plastic buckets with holes in the bottom and used clay pots. Containers should be about 20 litres in size. A variety of media can be used for planting, including compost, rice hulls, sawdust and chopped wheat straw. ‘Manure tea’ (water in which cured manure has been steeped) is one low-cost method to fertilise these media.

When fertilised and irrigated regularly, this strategy enables households with very limited access to non-saline soil grow vegetables throughout the year. HKI’s experience has been that homestead gardeners are at first sceptical that planting in non-soil media will work, and thus demonstration sites are critical to ensuring the practice is adopted.

Conclusions

This set of practices was identified to meet the specific needs of households in southern Bangladesh. However, most are applicable to the growing number of areas in the world where poor households are affected by increased soil salinity. Most methods are very low cost and, with the exception of promoting new varieties, can be achieved with no additional inputs. The ability of households to replicate all practices was increased by working through Village Model Farms, which offered demonstration sites and a space for meeting and training to all homestead gardeners in a village.

Considering effectiveness in mitigating soil salinity and low cost to beneficiaries in terms of labour, money and time, mulching and planting of seed beds are highly replicable strategies that can be easily integrated into any HFP programme. Digging and treatment of pits for crop plantation are also very effective and most households do not find it to be overly labour intensive. However, introducing this practice requires a relatively high level of expertise by programme staff in order to demonstrate the correct method of soil management and planting for various types of crops. Composting is a practice that poor households have found more difficult to adopt. Properly managed compost pits require allocation of appropriate space (which can be scarce on small homesteads) and ongoing effort to maintain. Nonetheless, composting is very effective in mitigating soil salinity and increasing soil water-holding capacity. A key component of healthy gardens, composting also brings other benefits such as discouraging the use of chemical fertilizers and increasing crop productivity in any environment. It is therefore worth developing tools and techniques to promote composting in areas where vegetable cultivation is a priority strategy to increase nutrition and income for poor households.

For more information, contact: Erica Roy Khetran, email: ekhetran@hki.org

Reference this page

Erica Roy Khetran (). Helping homestead gardeners mitigate the impact of soil salinity. Field Exchange 44, December 2012. p63. www.ennonline.net/fex/44/helping

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