Pesticides have the potential mobility from the site of application to natural water resources leading to surface water quality problems. Binding pesticides to soil lead to immobilization preventing their mobility into surface water and enhancing their availability for degradation by soil microorganisms and their secreting enzymes. The impact of low-cost organic amendments used in agricultural operations on the persistence of three pesticides; devrinol, diazinon, and trifluralin in agricultural soil was investigated. Pesticide residues in sewage sludge (SS), farm compost (Comp), and no-mulch (NM) control treatment following field application were monitored at different time intervals using solvent partitioning and gas chromatographic procedure (GC). Half-life (T<sub>1/2</sub>) values of the three pesticides in soil were determined under three farming practices to investigate how long each pesticide remains in each soil treatment. Results revealed the retention of devrinol by 30%, diazinon by 55%, and trifluralin by 80% in soil amended with SS compared to sole NM soil used as control treatment. This practice might prevent the off-site movement of pesticides. Devrinol T<sub>1/2</sub> value of 14.1 days was significantly (P≤ 0.05) lower in soil amended with Comp compared to SS amended soil due to its high dissipation constant (K). Diazinon residues fluctuated during the first week after spraying and started to decline, reaching a minimum value of 0.004 µg g<sup>-1</sup> soil at 35 days after spraying. Its T<sub>1/2</sub> value of 10.6 days was significantly lower in SS amended soil compared to Comp waste and control treatments (15.8 and 18.5 days, respectively). Trifluralin residues in NM soil showed a low dissipation constant and greater (T<sub>1/2</sub>) value of 116 days. Its dissipation and degradation in soil amended with Comp and SS indicated half-life (T<sub>1/2</sub>) values of 48.5 and 34.6 days, respectively. The low adsorptive capacity of devrinol due to its high-water solubility requires minimizing its application rates in agricultural regions to prevent environmental contamination of natural water resources.