his study evaluates climate efficiency in maize cultivation (Zea mays Sahara yellow) considering the use of nitrogen fertilisers (NPK 14-14-14) and biochar in the soil. The problem formulation was how to identify significant results on the study of climate efficiency in maize cultivation using nitrogen fertilisers and biochar in the soil. The objective was to verify the benefits of using biochar in the efficiency of nitrogen fertilisation, namely urea coverings. The focus was on optimising root growth, plant height, germination rate and biomass, in a randomised block design (RBD). The effect of various proportions of biochar (1%, 3%, 10%, 50% and 100%) with conventional substrate was evaluated in five blocks to determine its impact on parameters such as germination, height, number of leaves, root length and weight, and shoot weight. Different proportions of biochar (BPI and BPA types) with coarse (≤ 9.5 mm), medium (9.5 mm < 4 mm) and fine (4 mm < 2 mm) particle sizes were tested in various combinations with substrates, evaluating parameters such as root and aerial part weight, plant height, number of leaves, and root length, using pots controlled under constant environmental conditions. They were analysed during an experiment conducted from 24 January to 14 March 2025 at the Rural Engineering Laboratory/Mitra. The results indicated that moderate concentrations (1% to 3%) of biochar, especially in fine particle size, enhance root growth and the efficiency of nitrogen fertiliser use, in addition to improving soil structure and water retention, contributing to agricultural sustainability and greenhouse gas mitigation. It was noted that the combination of biochar with suitable substrate favours plant development, while high concentrations of biochar (100%) without substrate limit growth, highlighting the need for balanced doses. These practices promote climate-smart agriculture, increasing productivity and reducing environmental impacts, providing support for technical recommendations and sustainable soil management policies.