Assessment of farmers' knowledge on balanced fertilizer use in vegetable-based cropping systems

Abstract:

A farmer who has grown vegetables for three decades is not automatically a farmer who understands what balanced fertilization actually requires, and this challenge to assumed expertise motivated a structured knowledge assessment across vegetable-growing communities around Thies, Senegal. A survey of 312 vegetable farmers assessed knowledge across five fertilizer management domains: soil testing before fertilizing, correct nitrogen-phosphorus-potassium ratio, fertilizer application timing, micronutrient needs, and combined organic-inorganic fertilizer use. Overall knowledge scores averaged 42.6%, with farming experience showing a non-linear relationship to knowledge score, rising through the first two decades of farming experience before plateauing and, among the most experienced farmers, declining slightly, suggesting knowledge accumulation through practice alone reaches a ceiling without complementary formal training input. Fertilizer timing knowledge was the strongest domain, with 51.4% of farmers demonstrating adequate understanding, while micronutrient knowledge was the weakest, at just 19.8%. Information source analysis showed fellow farmers as the most common knowledge source at 31.2% of respondents, ahead of extension officers at 26.4%, with 11.0% of farmers reporting no formal information source at all. These findings identify micronutrient management and reliance on informal peer-to-peer knowledge transfer, rather than experience level itself, as the more binding constraints on fertilizer knowledge in this farming community, pointing toward targeted extension programming on micronutrients and stronger extension service reach as priorities for improving fertilizer management practice among vegetable growers in this region.