Question

why do substances produce Flames of different colours

Answer 1

the bright Orange of most wood frames is due to the presence of sodium which when heated emits the light strongly in the Orange. debut in the wood films come from the carbon and hydrogen which emits in the blue and violet colour
instead the colour of the Flames in a wood fire due to different substance in the flames and the substance which is burn

Answer 2

hey friends here is your answer
depending on ignition temperature
nature of material a substance produce Flame of different colours