Best harvesting practices for farmers
Type de pratique Reduce
Nom de la pratique Best harvesting practices for farmers
Nom de l’acteur principal Farmers
Type d’acteur(s) Cultivateurs
Pays South Africa
Etape de mise en œuvre Récolte, Stockage
Année de mise en œuvre 2010
Opérations déjà accomplies/en cours Not only do the African staples cassava and yam have a short shelf life, there is little tradition of transforming them into
more stable products such as flour, so they rot in the barns of the hungry. The sweet potato – the world’s seventh most important
food crop – has a high water content, making it more prone to decay than dried cereals. In rich countries that have
advanced storage facilities, sweet potatoes can be kept for up to one year, whereas in sub-Saharan Africa, as much as 79
percent of a stored tuber crop can be lost during the same period of time. Nevertheless, careful design of storage systems,
as well as measures such as removing stems from the tops of the potatoes, have been shown to improve recovery of the
crop by up to 48 percent. Recent work has helped identify the exact point in the crop’s maturity (at 105 days) that it is best
to harvest the tubers to maximize productivity, nutritional quality, storage properties and consumer acceptability. Changing
the way African farmers harvest tubers can help them feed their families while at the same time opening up new opportunities
to capitalize on the growing demand for fresh produce in urban centres. They often have no dedicated storage facilities
and, instead, keep potatoes on earthen floors in their mud and thatched huts where they can be exposed to sunlight.
This can lead to significant losses due to greening and sprouting, especially when doors are regularly opened and closed
during the day. Cold storage of tubers as practiced by large-scale growers worldwide may not be an appropriate or affordable
technology for these farmers, so a viable alternative is to leave crops in the ground for longer periods after maturity, and
to harvest them in batches sequentially, rather than all at once. This can help distribute farm labor inputs and income while
helping to meet quality standards for commercial sales. One study in South Africa compared losses from traditional harvests
stored in farmers’ stores with sequential harvesting, leaving potatoes in the ground for up to six weeks after maturity. In
the best instances, sequential harvesting cut wastage from 37 percent of the harvest down to just 11 percent – a 71 percent
reduction in losses. On average throughout the year, 8 percent of the entire crop was saved through sequential harvesting.
Résultats et impacts One study in South Africa compared losses from traditional harvests
stored in farmers’ stores with sequential harvesting, leaving potatoes in the ground for up to six weeks after maturity. In
the best instances, sequential harvesting cut wastage from 37 percent of the harvest down to just 11 percent – a 71 percent
reduction in losses. On average throughout the year, 8 percent of the entire crop was saved through sequential harvesting.