Flowering phase

Probably a dumb question but has anyone experimented with changing the amount of darkness needed to trigger flowering?

Long story why, but it would help my situation out tremendously if I could do 13 hours on and 11 off. Even 12.5 hours on and 11.5 off would help some.

I think the exact amount is going to vary by strain and pheno. Are you already and flower and want to increase the light duration? I'm not sure why you'd want to, but you already said long story lol. If you aren't in flower yet, try 13/11 and see if they flower.

How old is plant?
From seed or clone?
How long did you veg?
You see preflowers before flip?

I think I saw something about that talk to @lime73 think he was talking about it but not sure he is a good guy for help as always thank you for your time and good luck

I was in a thread recently where it was flowering for them at 14 hours. Why do you want the lights on longer than 12 hours? Seems like you would get more spacing in the bud and spend more money growing.