Critical Period purpose and duration

I live near the equator and while in veg my plants were on 18h light and 6h dark. On evenings, I had extended the amount of light plants were getting by putting them in my grow room while the sun was going down. After a while, I switched my light pattern to trigger flowering by moving plants on 18h dark and 6h light. It had worked, showing white pistils in about 2 days and then I decided to put them on the natural 12/12 cycle that my environment provided.

My plants seems to be growing fine and is in 1 month of flowering. I’ve been reading and it said that any flowering plant do better in more darkness provided.

  1. Does it matter that I changed it from 18h dark to 12h dark? I am assuming it shouldn’t matter long as it stays within the critical period (correct me if I’m wrong)

  2. Is the critical period’s only role to trigger plants to flower or is it to begin and continue the flowering process?

Just want to provide plants with the best so let me know!

Keep it at 12/12

I would imagine that being dark for to long would make it grow less yield as it wont have enough light to make what it needs to grow.

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Like stated 12/12 should give you the best amount of sunlight for bulking your plant up.

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Thats interesting. Makes me wonder what’s the purpose of dark periods

@Hellraiser Your thoughts?

No harm done as you switched to 12/12 after initiating flowering with the extended dark periods. That can trigger a more rapid flowering response but for max bud growth, you do want to stay on/near 12/12 for most of flowering.

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It triggers your plant to release hormones to send it into bloom. The hormones continue to be released as long as the dark period stays in range; without the minimum of hours of darkness, the plant will not bloom or stay in bloom. If you change the photoperiod length too much while they’re blooming, you can potentially hermie your plants, so be careful.

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Ah we definitely don’t want that to happen

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I wean down I start at 12/12 and slowly shorten I’m almost at end of week 4 flowering doin probably 10.75 11 hours of light just like in nature it keeps getting darker I had a plant that was super slow to flower untill it had a solid 13 hour sleep for a few days

There’s a theory of simulating incoming winter with days and lights in time shorting closer to harvest heard of lots of ppl doing a 15 hour night near the last 2 weeks of flowering

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That’s interesting. I would have tried things to see for myself but I don’t have the time, proper measuring gear, growing gear for consistent results and amount of plants (due to the allowable amount) to try and see the results.

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