The main concept of drip irrigation is to create a continuous wetted strip directly beneath the soil where the active roots are concentrated. The fertigation allows application of right amounts of plant nutrients uniformly to the wetted root zone. A field experiment was conducted to evaluate the effect of different fertigation levels and depth of laterals under plastic mulch on the performance of Amaranthus (Amaranthus hypochondriacu, variety: kannara local). The yield showed significant difference with different levels of fertigation and depth of laterals. Based on the statistical analysis the study suggested that treatment of 80% fertigation and 10 cm lateral depth is better due to the fact that it gives higher crop yields ( t/ha) with substantial saving in fertilizer usage. Hence, subsurface drip irrigation of 10 cm lateral depth with 80% fertigation level under plastic mulching for amaranthus is a good option. | Optimization of lateral depth of subsurface drip fertigation for amaranthus