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Iodine (I) is an essential micronutrient, which plays a critical role in human metabolism. However, its concentration is known to be low in most soils, making it deficient in crops. With most I agronomic biofortification studies conducted under controlled environments, limited information currently exists on this approach of enriching I deficient crops under farmer field conditions. Two-year field experiments were conducted in 2017 and 2018 to examine efficacy of cowpea and cabbage in the uptake of foliar applied potassium iodide (KI) and potassium iodate (KIO₃), each with 0, 5, 10, and 15 kg I ha⁻¹ under farmer field conditions. Results indicate that KI was 34% more efficient than KIO₃. Iodine concentration increased with application rate. In cabbage, the lowest I concentration (8.2 mg kg⁻¹) was registered at 5 kg I ha⁻¹ with KIO₃ while the highest was 109.1 mg kg⁻¹ at 15 kg I ha⁻¹ with KI. Cowpea registered the lowest I concentration of 531.5 mg kg⁻¹ at 5 kg I ha⁻¹ with KIO₃ while the highest (5854.2 mg kg⁻¹) was registered at 15 kg I ha⁻¹ with KI. Therefore, cowpea and cabbage can be effectively biofortified through foliar application of both KI and KIO₃ under farmer field conditions.