How Long Should I Leave Weed Grow Lights On A Day?

Leaving Grow Lights on 24 Hours: Is it Recommended?

Indoor growers are always looking for ways to increase the health, growth, and output of crops. One method many have heard to accomplish this is to allow grow lights to stay on 24 hours a day.

It is not recommended to leave your grow light running for 24 hours straight. Twenty four hours of light can prevent a plant from effectively carrying out the respiration process.

If your plant is not responding to 12 or 18 hours of light, you may need a stronger grow light or you may need to feed your plant nutrients.

Indoor Vegetative Light Period for Maximum Yields

Growing your plants indoors means you get to manipulate your environment as much as you want. When growing indoors, you can essentially keep your plants in the vegetative stage as long as you desire by keeping plants under light 18–24 hours each day.

Flowering Stage

Cannabis starts budding when plants get at least 12 hours of uninterrupted darkness each night. After plants start budding, they must continue to get long dark nights until harvest or they may revert back to the vegetative stage.

Indoors Flower Light Period for Maximum Yields

Indoors most growers put their plants on a 12–12 schedule to initiate flowering. Outdoors the plant will naturally start budding in late summer when nights are growing longer and longer as winter approaches. Just make sure plants aren’t exposed to light during their dark period!

What is 12–12 Lighting?

The indoor grower will need to artificially induce flowering/budding in plants by changing the grow light schedule so the plant receives only 12 hours of light a day, and 12 hours of uninterrupted darkness.

Once the plant is changed over to the flowering (12/12) light schedule, there is generally another 6 weeks-5 months (average 2.5 months) before the plant’s buds are ready for harvest.

Conclusion: leaving the lights on 24 hours — yes or no?

Now we get to process the deeper knowledge & information:
The 24-hour periods are very good for the vegetative stage if you’re trying to maximize the growth, but you should be careful not to overdo it because the plant won’t have the proper growth process and eventually will become prone to illnesses and will yield lower-quality results.