Cineraria (Senecio cruentus) are admired flowering potted plants due to their wide range of colors. It is considered as very sensitive to water stresses. Pot experiments under open field condition. were conducted during the two growing seasons 200412005 and 200512006 at the Experimental Station of Ornamental Plants. Fac. of Agric.. Mansoura Univ.. to investigate the effect of different irrigation water regimes and composts application as soil conditioners. prepared from rice straw. cotton and maize stalks. as well as their interactions on growth. flowering and chemical composition of cineraria plants. Crop-water requirements were based on Class-A pan evaporation . however. four irrigation treatments were tried: Ep 0.6. Ep < /p> 0.8. Ep 1.0 and Ep 1.2. which were equivalent to the applications of 60%. 80%. 100% and 120%. respectively. of the evaporated depth of water from Class-A pan. Results indicated that although all the amount of irrigation water treatments improved the growth and chemical composition (ChlorOphyll a and b mgig f.w.. nitrogen percentage and its uptake). irrigation application equal to 120% of Class A pan evaporation depth proved to be the most favorable as the maximum content of chlorOphyll and nitrogen uptake were improved. Regarding soil conditioners. several characters were improved due to composts addition such as plant height. leaf area, both number of branches and flowers per plant as well as diameter of display (cm). In addition. results also. showed that the contents of chlorophyll a and b and nitrogen in leaves were significantly increased as a result of composts application. 0n the other hand. porosity and saturation percent values increased with the addition of soil conditioners. but bulk density take the opposite. For the best vegetative growth and flowering of cineraria plants. it may be recommended to be irrigated equal to 120% of Class A pan evaporation depth using maize compost as soil conditioner with a rate of 0.2 kgipot.