This study has been carried out through three successive seasons (2012, 2013 and 2014) on 12 years old Manzanillo olive trees in a private orchard located at 50 km of Cairo – Alexandria road in north-west of Egypt. The main objective of this study was to improve the physical and chemical properties of olive pomace by adding microorganisms specific to phenolic substances, which leads to their disposal and suitability for cultivation. Two microorganisms (Trichoderma virdi and Pseudomonas fluorescens) were evaluated to determine their promoting effect on the growth and productivity of olive trees. The experiment consisted of 9 treatments, 2 trees per treatment replicated 3 times in a randomized block design. Data exerted that, the treatment with compost 50 % + Pomace 50 % + Pseudomonas fluorescens gave the highest fruit set (%), yield, remaining fruits and leaf nitrogen and potassium. While, using the compost 75% + pomace 25 % + Trichoderma virdi + Pseudomonas fluorescens recorded the highest number of leaves and inflorescence/meter.

Conclusively, it could be recommended under the same conditions of this study, using pomace (olive mill wastes) at the rate of compost (Comp.) 50 % + Pomce (Pom.) 50 % + Pseudomonas fluorescens (Pseu.) to increase the productivity of Manzanillo olive trees.