Optimizing container cell size and nutrition is crucial for enhancing the quality of vegetable transplants. The current study evaluated the effect of different cell sizes and Ca(NO3)2 on some properties of tomato (Solanum lycopersicum L.) transplants. Experimental treatment included four levels (0, 50, 100, and 150 mg L–1) of Ca(NO3)2 and 5 different cell sizes of containers (1, 2, 3, 4, and 5) in a factorial experiment based on a completely randomized design (CRD) with three replications under greenhouse conditions. Ca(NO3)2 and larger cell size, increased height, stem diameter, fresh and dry weights of roots and shoots, and concentration of chlorophyll, protein, SPAD, carbohydrates, and macro/micronutrients. The results revealed that maximum shoot and root fresh and dry weight, photosynthesis pigments, N, P, K, Ca, and Fe concentrations were recorded at 150 mg L–1 × cell size 5. In comparison, the highest Zn and Mn concentrations were recorded at 100 mg L–1 × cell size 4 and 5. Our results demonstrated that applying Ca(NO3)2 and increasing the cell size of the containers improved the traits evaluated, so Ca(NO3)2 at 10 and 15 mg L–1 with cell size 5 can be recommended to transplant producers.
