LED Grow Light

Leaving Grow Lights On 24 Hours: Right Or Wrong?-Part II

There’re some pros and cons to leave the grow lights on 24 hours. Then, what is the best way to provide more light?

The Best Way To Provide More Light

As mentioned, the only real advantage to running your lights all night long is that it allows you to provide your plants more light throughout the day, without having to buy new or additional lighting equipment.

But if your plants are not getting enough light, you should buy new lights. These can either be lights to replace your old fixtures, or ones to run in addition to your existing plant light fixtures.

If you don’t have sufficient light for your plants to grow properly during vegging, you certainly don’t have enough for them to produce a good yield during flowering. You’re going to need more lights anyway. There is really no point in running your existing lights 24/7 during vegging and compromising the plant’s health as a result. Just get additional lights. Shop

The Best Lighting Schedules For Cannabis

We’ll start with flowering, because there is no flexibility to increase the daylight hours during this stage. Your lights need to be off for 12 hours per day (with the exception of autoflowers, of course). Keeping them on longer can result in your weed plants switching back to vegging and then you’ll have a hard time getting them to flower again.

During vegging, you have much more flexibility. It is perfectly possible to leave the lights on overnight, but as mentioned, it is best to give your plants at least some darkness. The most common lighting schedule during vegging is 18 hours of light and 6 hours of darkness. This is the schedule we recommend. 20 hours on and 4 hours off works well, too.

Another interesting option is to use a 6/2 light schedule. What this means is you leave the lights on for six hours, then turn them off for two. You have 3 of these cycles per day. You still end up with 18 hours of daylight and 6 hours of darkness, but they do not all fall at once.

Do Autoflowering Plants Need A Dark Period?

Yes, autoflowering marijuana plants they need time to rest, just like any other plant. Then main difference with autoflowering cannabis strains is that they switch to flowering automatically. They do not need you to shorten the daylight hours to tell them when to switch.

Theoretically, you could run the lights 24/7 even during flowering, but you shouldn’t. However, you can run them on an 18/6, or even a 20/4, cycle during the bloom stage, the same as during vegging.

Should Seedlings Get 24 Hours Of Light?

No, they should not. Seedlings also need a dark period. We recommend leaving the lights on for 16 hours a day for seedlings.

Leave Grow Lights On 24/7: Final Thoughts

Leaving your grow lights on for 24 hours a day increases the total amount of light your plants receive during the day, which leads to faster growth. But your plants will likely be weaker and more susceptible to disease.

If you want to give them more light, you should add additional grow lights or replace your existing ones with more powerful fixtures. This will give you far better results than simply leaving the lights on longer, which you won’t be able to do anyway, once you are into the flowering stage. If you want to add led grow lights, our shop will help you find the right ones. Shop

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