Finding Hibiscus sabdariffa L. crop coefficients Kc under irrigation in Tropical Savannah

Hibiscus sabdariffa L.is one of the most promising cash crops in African Tropical Savannah that needs production under irrigation in the dry season. The present study worked on the determination of the crop coefficient Kc and the growing stages required factors for the irrigation of Hibiscus, a plant providing a well-appreciated calyx used to produce a red beverage and for improving the taste of cakes. The crop coefficient Kc was calculated following a precise process. To begin with, an automatic weather station measured the six variables needed to compute the reference evapotranspiration ET0. Then, to scientifically ascertain the results, the study ran 9 lysimeters to determine the crop maximum evapotranspiration ETM. These 9 replications were filled with a unique well-drained loam. ETM was determined using the water-balance equation based on the measurements of irrigation I, drainage D and stock variation ΔS. Finally, the definition ETM = Kc·ET0 was applied. The results showed that the triplet {stage name; stage duration (days); crop coefficient (Kc)} values were respectively {initial; 30; 0.3±0.03}; {development; 37; 1.0±0.14}; {mid-season; 21; 1.7±0.09} and {late-season; 22; 1.5±0.05}. These results fill a knowledge gap about the production of Hibiscus under irrigation during the dry-season in Tropical Savannah