wrong section try beginner growing but to answer your question im pretty sure all plants need some time in dark and light so like 12:12 during the vegitation stage and and then more light when u try producing buds ps. correct me if im wrong im pretty beginner my self at growing only a couple outdoor grows which didnt satisfy me that much =\
Technically, I think you can put autoflower plants under 24 hours of light. But, I think they tend to do better with a 20/4 or 18/6 light cycle. Good luck.
Ummm. I think this is the beginner section. This doesn't make any sense. Why would you 'veg' with a shorter light cycle than you flower with?