Improved nutrient management regime for open field production of sweetpotato seed

This two-page research brief presents findings from 2023 field trials in Eastern Uganda testing fertilizer and spacing combinations for certified sweetpotato seed production under commercial seed producers. Results show that NPK (25:5:5) and Forest Compost + (NPK + Decomposed Poultry Manure) significantly enhanced vine yield and total stem length. NAROSPOT 1 recorded the highest vine multiplication rate (VMR), and closer spacing (20 × 10 cm) yielded more vines without significant difference from 20 × 15 cm. The study recommends optimized nutrient management to boost vine productivity and seed-system profitability.