Olea europaea, a native plant of the Mediterranean region, is of great interest to agronomists worldwide, owing to its health beneficial properties and tolerance to harsh environmental conditions, along with its economic importance. The productivity and production efficiency of olive is linearly related to both the level of transpiration and the amount of water supplied. Under conditions of limited supply of good quality water for irrigation in Kuwait, deficit irrigation applied at selected phenological stages can maximize economic gains and minimize environmental damage. Moreover, mulching contributes to a significant reduction in water requirements via reducing soil water losses and increasing soil water retention. In this study, the effects of different irrigation levels, a restitution of 50%, 75% or 100% of the estimated evapotranspiration rate (ETc), and the application of mulching on plant growth under the Kuwait environmental conditions were determined to evaluate the possibilities of reducing the amounts of water supplied with irrigation. Various parameters determining the vegetative growth of the trees such as average height, stem girth and number of branches were recorded at three months intervals. Both the irrigation level and mulching were shown to possess a significant impact on growth of Sourani olive cultivar under the Kuwait environmental conditions. Statistical analysis revealed no significant difference in the height of the trees under all the three irrigation treatments with mulch and trees under 100% ETc devoid of mulch. In contrast, a significant difference was exhibited by trees under 100% ETc with mulch and 50% ETc without mulch. Within each irrigation treatment, trees with mulch presented higher values for plant height, stem girth and number of shoots. Thus deficit irrigation of 50% ETc along with organic mulch was shown to enhance vegetative growth close to its maximum potential by conserving the scarce water resources.