This study was carried out during the two successive seasons of 2018 and 2019 at Somosta, Beni-Suef Governorate, Egypt, to evaluate the effect of irrigation intervals, foliar application of potassium silicate and seaweed extract on vegetative and flowering growth parameters and essential oil percentage of Tagetes patula plants. Plant height (cm), number of branches, stem diameter (mm),leaf area (cm²), plantfresh and dry weights (g), flowering date, number of inflorescences/plant, inflorescence diameter (cm), inflorescence fresh and dry weights/plant (g) and vase life/days were significantly decreased with rising intervals of irrigation. Irrigation regime of four days interval gave the earliest flowering. The results cleared that, foliar applications of seaweeds extract at 3 ml/l and 5 ml/l, potassium silicate at 3 ml/l and 5 ml/l significantly affected all studied parameters compared with control. The magnitude of increase is more pronounced by applying combination between potassium silicate and seaweed extract treatments at the high concentration. The most pronounced effect for the interaction was that found between potassium silicate at 5 ml/l plus seaweeds extract at 5 ml/l when plants irrigated every one or two days where the highest vegetative and flowering growth parameters and essential oil percentage were recorded in both seasons. So, it is advisable, to reduce the effect of drought stress, treating tagetes plants with high concentration of potassium silicate and/or seaweed extract each at 5 ml/l