As the name suggests, autoflowering cannabis strains automatically flower with time, no matter what light schedule is received. However, ensuring they get enough light is essential if you want a decent yield. These plants keep things simple for growers, and can be a great start for beginners. Photoperiod plants, which many growers are familiar with, are the opposite and require special light schedules to jump start the plant into flowering mode.
Most agree that giving 18-24 hours of light is ideal.
As autoflowering plants do not rely on hours of light to tell them when to flower, they can be subjected to a 24- hours of light throughout their growth cycle. In fact, many growers believe 24 hours of light is crucial when growing autoflowering plants, as it may give them the best chance to grow bigger in the vegetative stage and then eventually flower accordingly.
Cannabis is classed as a C3 plant, meaning it can absorb CO₂ during periods of light for photosynthesis. This theoretically eliminates the need for darkness, as they do not need periods of dark to photosynthesis, unlike C4 plants. Autoflowering plants have also evolved in the northern areas of the world where they receive near to 24-hours of light as standard during the seasons of growth. As such, it is safe to say that autoflowering cannabis can thrive under 24-hours of lighting.