Hoan and sweetpotato: a sweet, budding love affair
From the Field
A single parent to two children, Nguyen Thi Hoan from Village 6 in Quang Thach commune, Quang Trach district, Quang Binh province is a hardworking, open-minded farmer. Having migrated from another commune into Quang Thach, she owns small parcels of land – 1,500 m2 in the lowland, and 1,000 m2 in the upland – which she plants with rice, sweetpotato, and cassava. During off season, she works as construction worker to diversify her source of income.
Written by Hang Thi Le
A pioneer woman in shifting practices
Hoan started planting sweetpotato ten years ago, and had been bogged down by low productivity. She was very excited to have been selected to attend training activities on sweetpotato farming and planting material multiplication in net tunnel, organized by the FoodSTART+ (Food Resilience through Root and Tuber Crops in Upland and Coastal Communities of the Asia-Pacific) project and its partner IFAD investment program, SRDP (Sustainable Rural Development for the Poor). In her community, women are responsible for most of sweetpotato production and post-harvest activities; in her case, Hoan is responsible from land preparation, crop management, and harvesting, up to selling and processing the harvest.

Hoan at the first sweetpotato training organized by FoodSTART+

Training participants, including Hoan, are shown a stemborer-infested sweetpotato stem.
After the training, once back in the field, she started to change some practices.
As highlighted by training facilitators, using degenerated and infected planting material is one of the main reasons for low sweetpotato yield. Remembering this, Hoan shifted from planting materials that she used to obtain from her own field to higher quality planting material of an improved variety – yellow-fleshed variety – that she purchased from a neighbor. She paid VND300,000 (USD13.00) for getting new planting material, but she was confident it was going to help increase her productivity.
Another innovation in her farming practices was to change planting density. This year Hoan almost halved her planting density (using 60 kg of planting material for 650 m2 instead of 100 kg as in the past years). As she has learned, planting in low density reduces plants’ competition for nutrients, and allows them to grow better and to be less vulnerable to pests and diseases, eventually increasing the overall productivity of the system.
From applying nitrogen alone, she also started applying potassium and phosphorus. She had learned that potassium is one of the key nutrients for root and tuber crops cultivation, and one of the most important element for storage root formation and development.

Multiplication of sweetpotato planting materials are commonly done in open fields in the Quang Thach and Cao Quang districts. The image on the right shows two-week old planting materials grown in a “net tunnel.”
A crop for cash, food, and feed
These changes in farming and management practices have resulted in a significant sweetpotato production increase for Hoan. From an average production of 550 kg in the previous years, she harvested 1.2 to 1.3 tons of roots this year.

And as the roots were bigger and of better shape, she was able to immediately sell them to collectors and individual consumers, and got a lot of compliments for them.
Selling to collectors and individual consumers at a farm gate price of VND7,000 to 8,000 (USD0.31 to 0.35), she earned VND4.6 million (USD 204) from selling around 680 kg. The rest of the roots were given as gifts to relatives and neighbors, and some were sliced and sun-dried for her household consumption in the winter season.
The leaves and vines were used as both fresh and fermented feed for livestock.
Sweetpotato production costs and results before and after training
Descriptions/steps | Unit | Unit cost (USD) | Quantity/650 m2 | Amount (USD/650 m2 | ||
Before | After | Before | After | |||
Planting material | kg | 0.22 | 100.00 | 60.00 | Self-supply | 13.22 |
N | kg | 0.44 | 14.00 | 6.00 | 6.17 | 2.64 |
P | kg | 0.44 | – | 6.00 | 2.64 | |
K | kg | 0.44 | – | 9.00 | 3.96 | |
Manure | kg | 0.00 | 800.00 | 800.00 | Self-supply | Self-supply |
Pesticides | 0.00 | – | – | |||
1st land preparation: ploughing and harrowing | 650 m2 | 8.81 | 1.00 | 1.00 | 8.81 | 8.81 |
2nd land preparation: ploughing and harrowing | 650 m2 | 8.81 | 1.00 | 1.00 | 8.81 | 8.81 |
Planting and land preparation by human | day | 8.81 | 4.00 | 3.00 | 35.24 | 26.43 |
Weeding (human) and fertilizer apply | day | 8.81 | 2.00 | 2.00 | 17.62 | 17.62 |
Weeding by cattle power | day | 8.81 | 0.50 | 1.00 | 4.41 | 8.81 |
Harvesting by human | day | 8.81 | 1.00 | 5.00 | 8.81 | 44.05 |
Harvesting by cattle power | day | 8.81 | 0.50 | – | 4.41 | – |
Input cost | USD | 89.87 | 137.00 | |||
Sweetpotato production | Kg | 550 | 1,200-1,300 | |||
Income | USD | 0 * | 204 |
* Note: The farmer used the harvested roots for household consumption since she was unable to sell them due to their poor quality (small, unacceptable shape, and damaged by weevils).

Hoan feeds her cattle fermented sweetpotato.

Boiled sweetpotato is a favorite snack.
Hoan’s and her community’s sweetpotato future
After such results, Hoan considers sweetpotato as her top crop income earner, higher than rice. She plans to expand sweetpotato production in the coming years, if she manages to overcome land availability constraints. She is optimistic about getting higher yield, especially after the establishment of a net tunnel for multiplication of good quality and disease-free planting material in her commune by the FoodSTART+ project. “If I have access to clean planting materials, yields will certainly get better,” Hoan says.
Requiring a relatively small amount of investment and offering quick returns, sweetpotato holds a great potential in supporting women from poor households to increase their incomes. Hoan’s success has encouraged other women in the village to follow suit in her farming practices. She is recognized as an innovator, and is very happy to share her experience with friends and relatives. Now a training facilitator in sweetpotato production, she will have an even bigger opportunity to share her knowledge, skills, and practices to many others within her commune.
Photos by Hang Thi Le / CIAT
Funded by the International Fund for Agricultural Development (IFAD) and European Union (EU), FoodSTART+ aims to enhance food resilience among poor households by introducing root and tuber crops innovations. Outside of Vietnam, FoodSTART+ has activities in the Philippines, Indonesia, and India. It is coordinated by the International Potato Center (CIP) and implemented in collaboration with CIAT, in the framework of the CGIAR Research Program on Roots, Tubers and Bananas (RTB).