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What is the best light cycle for growing cannabis? The answer may surprise some while others will firmly nod their head in agreement.

First, what are the different light cycles? Cannabis starts out in the germination phase and then moves through the vegetative and flowering phases. If you’re growing cannabis outdoors or using autoflower seeds, controlling the light cycle is a non-issue. But for the rest of you, it’s important to know that until your plants reach their flowering phase, they need at least 18 hours of light and 6 hours of darkness each day. This is also known as the 18-6 light cycle. Some growers will give their plants 24-hours of light and 0 darkness hours throughout the vegetation stage. What’s the difference? In my experience, not much. There was really no difference in growth. The only difference is with the 24-0 light cycle, my electricity bill was much higher.

In the flowering phase, the amount of light should be reduced to 12 hours of light and 12 hours of darkness. This is known as the 12-12 light cycle. To control these cycles without having to run into your grow room constantly, I recommend getting a 24-hour timer. Timers are great for automating your light cycle and they are easy to use. There are a couple different styles to choose from – mechanical and digital are the two most popular ones for indoor gardening. There’s even timers with 8 outlets so you could put your other grow equipment on the same schedule. The important thing is not to buy a cheap no-name one. These timers need to work all day long and you don’t want a crappy timer that fails on you. Here are the best 24-hour timers for indoor grow rooms:

Some growers have even experimented with a 11-13 light cycle for the flowering stage. Landrace cannabis strains grown in tropic regions are naturally on a 11-13 light cycle and they grow fantastic. Is a 12-12 light cycle for flowering better than a 11-13 light cycle? Most people say the 12-12 light cycle is better because more parts of the world are naturally on a 12-12 light cycle. Other growers who have experimented with 11-13 claim they get better flowering production and trichome production on their plants. This is absolutely one of those topics that can be heavily debated. In conclusion, a 18-6 light cycle is best for plants in the vegetation stage and autoflower plants since a 24-0 light cycle doesn’t really lead to better growth – just a higher electricity bill. For flowering, a 12-12 or a 11-13 light cycle can both work great. A 11-13 light cycle may lead to better flower and trichome production but there isn’t really any proof of it – so it’s pretty much just an opinion from some. What do you think the best light cycle is for growing cannabis? Let me know by leaving a comment below!