The question on which the idea of the work was based is: Does soaking sugar beet seeds in solutions or extracts of substances known in many previous works for their effects on enhancing growth lead to changes in the plant's performance throughout the growing season, reaching yield and quality? And the most important point is to monitor this effect under the challenges and obstacles of commercial production. Sugar beet is grown in the clay soils of El-Minya Governorate (one of the Central Egypt governorates) in a way that can be described as the most random in the world, but the fact that cannot be overlooked is that the sugar beet productivity under these conditions is high and exceeds the global average. Concentrations of 150 ppm gibberellic acid (T2), 500 ppm spirulina extract (T3), and 500 ppm potassium humate (T4) were used to soak the seeds of two sugar beet varieties (Husam, and Sahar). The effect of these treatments was studied and compared to the conventional method (without soaking: T1) in two field experiments at Mallawi Agricultural Research Station, El-Minya Governorate. A factorial experiment with a completely randomized block design in three replicates was applied during the 2020/21 and 2021/22 seasons. The obtained results showed the superiority of T2 in leaf area index, leaf area duration, and total dry matter. While T3 showed an appreciable improvement in quality parameters and sugar yield. In most cases, the values of relative growth rate were significantly correlated to the values of net assimilation rate