Light time on bloom

Has anyone ever reduced the light time to a 10 hour on during bloom

Hello and welcome to the ilgm forums.
Has anyone ever? I’m dono if I can answer that accurately lol.

It’s not common thats for sure.
Why do you ask?

Lighting time has a small roll in cannabis development, it’s critical that photo period plants get a darkness of at least 12hr In bloom that leaves only 12hr to get radiation energy to grow buds.
This is where strength of light comes in, a large light can give more light in 10hr than a weak one can in 20hr!

So this is a deeper conversation than you may first be thinking.


Exactly what Nicky said.

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Welcome @Blake58. Strap in, these folks will teach you everything you need to know. The only problem is holding the top of your head on after a month or two :exploding_head:. But the results …top notch.

Fire away and good luck!!

Thank you it has been about 20 years since I grew things have came a long ways again thank you

The reason I ask is nature going into the fall days are shorter nights a little longer Was just wondering running a 600 watt hps for bloom will be thankful for any help

Shorter light cycle seems to help some long flowering plants mature a good bit quicker. A quick Google search on 10 hour flowering should get you a ton of hits. I’ve switch down to 10 hours before (for heat reasons) and still had a really good yield, but the first 6 weeks of flower was 12/12. Can’t really say the buds matured faster but they were good medicine.

Give it a try, worst thing that happens is you grow weed too fast right?

With the timers I have I can take about 15 minutes off about every week I think I Will leave on half days only a few weeks into the process since I’m a cheap prick had to sex them first then grow some more found a couple of seeds in some girl Scout cookie Want try this before buying some seeds I’m retired it more of a hobby at this point plus tired of buying it with time and effort should pay off hopefully thank you again

There is no benefit to slowly increasing dark period this has been discussed and studied, no commercial operation does this for good reason.

Although there is some speculation that some sativa strains do benefit from a longer dakr period such as 10hr lights on 14hr dark due to their natural environment the genrtics originate from. Again not proven to my knowledge but if you have strong enough lights you can manage a good DLI and still do this.

If your at all under lighting your plants (DLI learn it, it’s important use online calculators and a smart phone lux app taking an average of canopy readings) then ignore the longer dark period because your plants need that light energy.

You need to ensure strong enough light, it tells your plants they are being stressed because light degrades thc and thc is a plants protection from bugs/uv rays etc.
Photo period plants grow tricombs at night though.
So it’s all a balance.

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