Onset of Rainfall and Cumulative Analysis for Sorghum Cultivation in Baringo County

Abstract

Sorghum is an essential food security crop in the majority of the ASALs regions, such as Baringo County. This study investigated the critical relationship between rainfall levels and the initiation of sorghum planting, with the aim of identifying the threshold at which rainfall is considered sufficient for germination and optimal growth. This study used historical meteorological data from 1990 to 2022, field experiments, statistical analysis, and sorghum growth patterns to discern the trigger points for planting, which are essential for ensuring successful cultivation. This study uncovered alterations in rainfall onset and seasonal rainfall accumulation. The planting window in Baringo County varied significantly, with some dates falling above and below the average onset values of April 4<sup>th</sup> for the long rainfall season and September 24<sup>th</sup> for the short rainfall season. A short rainy season is not ideal for sorghum planting, as it typically receives less than 300 mm of rainfall, which is insufficient for sorghum production. The optimal planting time for sorghum is usually late March and early April. The study found that 36.4% of the long rainy season years had high production, 42.4% had normal production, and only 21% had low or no productivity. The years 2000 and 2018 experienced minimum and maximum rainfall amounts of 198.45 mm and 941.9 mm, respectively.