Light-converting material comprises a europium- and manganese-doped barium magnesium silicate in a matrix. Light-converting material comprises a europium- and manganese-doped barium magnesium silicate of formula (1) in a matrix: Ba3(1-x)Eu3xMg1-yMnySi2O8 (1) x, y = 0-0.3 but not zero An Independent claim is also included for a greenhouse lining comprising the light-converting material.