Postharvest practices are a major determinant of losses for green leafy vegetables like rape (Brassica napus L), which are vital for food security, nutrition, and livelihoods. In Zambia, these vegetables are largely produced in rural areas and transported to urban markets, where inadequate practices at various stages contribute to significant quality and physical losses. 

Key Findings

A study on the supply chain from Kanakantapa (Chongwe district) to Lusaka city revealed the following: 

Harvesting practices: Most farmers harvest manually and pile leaves in the field, leading to initial quality deterioration (see Figure 1). Few use rigid receptacles, risking physical damage to the leaves. 

On-farm storage: Around 44% of farmers load vegetables directly onto transport vessels after harvesting, while others store them for up to 12 hours in unsuitable conditions without cooling. Most use polypropylene sacks for storage and transportation, reusing these materials. 

Transportation: Open vans or trucks are widely used, with insufficient protection for the vegetables, resulting in compression and mechanical damage. 

Trading practices: Traders often sort and grade leaves upon arrival at markets. Most ensure freshness by sprinkling water but lack proper storage facilities, affecting quality and reducing sale prices. 

Benefits and Impact 

Harvest improvements: Proper receptacles during harvest reduce leaf damage and preserve initial quality. 

Storage upgrades: Innovations in cooling or humidity control can extend vegetable shelf life, minimizing postharvest losses. 

Transportation innovations: Enhanced packaging and transport methods prevent mechanical damage during transit. 

Grading systems: Incentives for quality grading can increase market value, benefitting farmers and traders. 

Practical Recommendations 

Innovate cooling and humidity control systems: Design low-cost cooling technologies accessible to small-scale farmers and traders. 

Introduce rigid harvesting receptacles: Promote scalable, farmer-friendly receptacle solutions to minimize leaf damage. 

Develop grading standards: Implement grading systems for green leafy vegetables to ensure premium pricing for higher quality. 

Enhance transportation systems: Innovate tailored transportation vessels and packaging solutions to minimize damage during transit. 

 

Contact information 

John Shindano, Twambo Hachibamba, Lukonde Mwelwa-Zgambo, Chiza Kumwenda, Mercy M. Mwale, Vincent Nyau and Aubrey Sadoki