Superabsorbent polymers based on rice husk (RHP) and loaded with urea (RHPU) can be used as soil conditioners to sustain sugar beet production in desert regions. Two field experiments were conducted in the Wadi El-Natron region, Egypt (longitude 30° 13' 0 E°, latitude 30° 25' 0 N) during the 2020/2021 and 2021/2022 seasons. A split-split plot design in a randomized complete block arrangement with three replicates was employed to study the combined effects of RHP and RHPU (0, 1g, and 3g), with three irrigation levels (IR100, IR80, and IR 60%) under a drip irrigation system on the physiological, yield and quality traits of five sugar beet varieties. The results indicated that the RHPU doses recorded higher values of leaf area index, net assimilation rate, relative growth rate, and root weight after 120 days of planting as compared to the RHP and controls (rice husk or untreated). RHPU application had a positive influence on the increase in root yield, under IR80% and IR60%. The interaction between RHPU (3 g) and IR60% showed a significant increase in the physiological traits, and root yield, compared to the IR100% control. No significant differences were observed in the interactions between RHPU doses + IR60% + Dina variety and RHPU3g + IR100% + Panther variety. Furthermore, a significant positive correlation was demonstrated between plant growth and yield, but not between quality attributes. In conclusion, the application of RHPU (0.5:0.5) improved the growth characteristics and productivity with the economic return of the sugar beet crop under the newly reclaimed lands.