black light during 12/12??

hey my first ? is if a black like disrupts and effects the plants during the dark cycle. i know that green light does not. also would a green party light bulb efect them?? i think its just coted green?? my other ? is i heard that you cant put plants into flowering until they have shown there preflowers or else you wont get any bud?? is this true.

black light bad, green light good..and no

okay thanks