Efficient utilization of water and fertilizers is necessary in agriculture in view of the shrinking resources and prohibitive cost of the inputs. Fertilizers applied under traditional methods of irrigation are not efficiently utilized by the crops. As an alternative, fertigation is gaining popularity all over the world. It was first started in late 1960's in Israel with the development of drip irrigation where over 75% of the irrigated area is currently fertilized by fertigation. Since then, fertigation has become very popular in many other countries. In India, about 3.12 lakh ha. Are under drip irrigation out of which 0.43 lakh ha are in Tamil Nadu. Fertigation is addition of fertilizers to irrigation water and application via drip or similar micro irrigation systems. Fertigation provides the plant nutrients directly to the active root zone, thus minimizing the loss of expensive fertiliser nutrients and improving their use efficiency. Which ultimately helps in improving productivity and quality of farm produce. Using brackish water (EC 6.2dS/m) in pulse (high frequency) irrigation, the yield of tomato was reported to be increased; but seasonal variations were observed wherein the yield got reduced during summer (Pasternak and De Malach., 1995). Under different salinity levels of the irrigation water viz., 1.1, 2.2, 2.9, 3.5, 4.2 and 4.9 dS/m, the water use efficiency in tomato got increased without any marked change in the soil salinity in the 0-90 cm soil. Further, with increase in water salinity level, the tomato seasonal accumulative water use decreased. Hence, it was reported that saline water with salinity from 2.2 to 4.9 dS/m could be safely applied in drip irrigation to tomato crop. In studies on the relative performance of the drip and furrow irrigation systems under different ET levels in clay soils (with EC ranging from 8.0 to 15.1 dS/m) irrigated with saline water (EC: 2.2 dS/M) had shown that the water productivity in cotton crop declined gradually with increase in the soil salinity up to 10.4 dS/m and there after it got drastically reduced at 15.1 dS/m and the reduction in the water productivity was still higher when the ET values exceeded 1.2 mm/day. Among the systems of irrigation, the magnitude of reduction in the water productivity in cotton was higher under furrow irrigation compared to drip irrigation, indicating that the saline waters used for conventional irrigation can be safely used for drip irrigation also. The reaction of water having high contents of Ca, Mg and HCO3 (hard waters), is alkaline with pH values between 7.2 and 8.5. The interaction of these waters with fertilizers causes diverse problems such as formation of precipitates in the fertilization tank and clogging of drippers and filters. In waters with high Ca content and bicarbonates, use of sulphate fertilizers causes the precipitation of calcium sulphate obtruding the drippers and filters.