**14. Electrical conductivity of the nutrient solution**

Similar to pH, electrical conductivity (EC) is one of the most important properties of nutrient solutions. The EC level between 1.5 and 2.5 dS/m is considered ideal for hydroponics/soilless culture. The strength of the nutrient solution strictly depends on the EC level of the solution. The total concentration of the solution is only indicated by the EC and not the specific nutrient components. Too high or too low EC level in nutrient solution may create salinity problems or the supply of some nutrients to the crop may be insufficient. Higher EC will not allow nutrient absorption to take place due to osmotic pressure and lower EC severely affects plant health and yield. However, among different species, the yield response of the plants may vary widely with respect to the EC level of the nutrient solution. So, the terms "too low" and "too high" need to be quantitatively defined for each cultivated plant species based on experimental results. When plants take up nutrients and water from the solution, the total salt concentration, i.e., the EC of the solution changes. Freshwater must be added If the EC is higher than the recommended range. Add nutrients if the EC is lower in the nutrient solution.

*Soilless Cultivation to Secure the Vegetable Demand of Urban and Peri-Urban Population DOI: http://dx.doi.org/10.5772/intechopen.102695*
