Calcium nitrate is 100% water soluble complex fertiliser consisting of 15.5% nitrogen (N) in readily available form and 18.5% calcium (Ca). Calcium is one of the secondary nutrients important for crop production and has role in improving colour, lustre and quality of fruits; soil structure and water infiltration in soil and protection against pests and diseases. Calcium helps activate cellular repair and plant defence mechanisms including selective cell death in advance of a potentially invasive disease that requires living cells and defence chemicals (e.g. phenolics and phytoalexins). High calcium levels also assist plant cells to with the formation of callose, plant cells providing protective barriers to injured plant parts. Calcium improves the function of antioxidants, protecting plant cells from biochemical stresses of cell damage. Calcium deficiency results in structure disintegration such as leaf tip burn, dying ends of shoots, detaching leaf stalks, blossom-end rot (in tomatoes and members of the cucumber family), bitter pit (in apples), increasing risk of pests and disease entry. The symptoms reflect the importance of calcium in cell structure but also the protective role of calcium against one of the plant‘s own enzymes that breaks down the pectin layer between cells.
