The correct irrigation frequency relies on the plant population density to increase yield and efficiency in water use. A field experiment was carried out in 2019 to study the effect of three irrigation frequencies, one (F1), four (F2), and eight (F3) days, and four planting densities, 20 (D1), 24 (D2), 28 (D3), and 30 (D4) plants per m², on the variables: soil moisture, actual water consumption, growth, grain yield, and water productivity of beans (Phaseolus vulgaris L.). The soil water balance was calculated based on the soil moisture, which was measured by tensiometers. The irrigation was done by a drip tape. The variation in soil moisture was greatly influenced by irrigation frequencies and planting densities in F3. Plant growth was not affected by treatments. Irrigation frequencies and planting densities have deeply affected the biometric and chlorophyll synthesis traits of beans. The highest yields were found in the treatments F1D3 (2968 kg ha⁻¹), F1D4 (2997 kg ha⁻¹), and F3D3 (2946 kg ha⁻¹). For water productivity, treatments with F1 irrigation frequency and the higher planting densities were more efficient in water use. Overall, the results are useful for technicians and farmers who work with irrigation management on beans.

Lately, irrigated soybean production has increased; therefore, tools that can aid water resources management must be improved. Two experiments were carried out, the first one from May to August and the second one from September to December 2019. The experimental design included randomized blocks with five treatments and four replicates. In the control treatment (SE), irrigation was carried out to meet the crop’s water demand during all growth stages. In the other treatments, irrigation was interrupted at specific crop growth stages (TI = VC-V4, TII = V5-R1, TIII = R1-R5, and TIV = R5-R7), and then restored. After calibration, the model satisfactorily estimated the canopy cover, biomass, and soybean yield, with high values of determination coefficients (r² > 0.90), low RMSE and MBE values, and high values of EF. In experiment 1, the soil water content was overestimated in the SE, TI, and TIV treatments by 0.24%, 0.78%, and 0.23%, respectively, and underestimated by 3.3% and 5.5% in the TII and TIII treatments, respectively. In experiment 2, in the SE, TI, TII, TIII, and TIV treatments, the soil water content was underestimated by 6%, 3%, 4.6%, 5.9%, and 6.7%, respectively. Real evapotranspiration was overestimated in all treatments in both experiments, with low r² values in both experiments 1 (0.11- 0.23) and 2 (0.04 - 0.21).