Sweet pepper (Capsicum annuumL.) plants were grown using Nutrient Film Technique (NFT) system with a nutrient solution of electrical conductivity (EC) 2 mS cm‐1. Higher conductivity levels of 4, 6, 8, and 10 mS cm‐1were achieved by adding concentrated KC1 solution to the basic nutrient solution. Higher ionic strength of the nutrient solution resulted in smaller sized fruit, reduced fruit dry weights, and decreased vegetative growth in terms of lower leaf area and specific leaf area (SLA). It also encouraged accumulation of more assimilates in shoots than fruits, decreased plant water consumption, leaf ψ, and fruit firmness. It increased leaf sto‐matal resistance, fruit dry matter content, fruit respiration and ethylene production, and advanced fruit colour change.