Can photoperiod plants flower automatically?

This is not a troll and I know it’s my first post and it might sound like I’m trolling but I have a concern about a plant. I’ve read lots of info online and the bible and I can’t find anything to help with this issue.

I got some seeds and sewed them earlier this year. I took cuttings from them in July and when the cuttings had taken root I put the adult plants to flower. The two adult plants (both photoperiod plants) were put on a 12/12 cycle and 2 weeks later they produced their first little tiny flowers. They finished flowering and everything was normal for them.

I kept 2 cuttings (1 from each parent plant) and they have been getting 16 hours of light and 8 hours of dark since then. I was trying to grow them on a bit before flipping.

I looked at them today and one of them has flowered. It looks like the flowers are about a week old. I checked them a couple of days ago and they didn’t have flowers then.

The lights are on a timer and they are on for 16 hours a day. Nobody has tampered with the timer, and only 1 plant has flowered, the other plant is still in veg mode. If the timer was messed up then both plants should be flowering. We haven’t had any power failures and for all intents and purposes the plants are getting 16 hours of light per day in one continuous session. Then 8 hours of darkness.

My understanding is if you take a cutting from an autoflower plant, the cutting should flower around the same time as the parent plant. This cutting flowered 3 months after the parent plant did so it’s not an autoflower.

My understanding of photoperiod plants is they won’t flower unless they get at least 12 hours of dark in every 24 hour cycle. It’s on 16 hours of light per day.

Any ideas what is going on?
Have I got an autoflower that provides cuttings that don’t follow standard protocol or have I got a weird photoperiod plant that decided it wanted to flower by itself whilst getting 16 hours of light per day?

Plants requiring 12/12 to flower isn’t the complete story. Photoperiod plants will flower once:

  1. the plant is sexually matured, and
  2. the light schedule is reduced.

Many plants are capable of flowering with a 15/9 schedule, it just depends on the individual plant’s genetics. Growers use 12/12 to guarantee flowering as some plants can be stubborn. A plant flowering at 16/8 is surprising, but apparently possible.

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The mum plant was on 16 hours of light for 3 months and she didn’t flower until flipped to 12/12. Should the cutting be the same or will it be older because it’s a cutting? And because it’s older is it more likely to self flower?

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Definitely odd but seems to be a possibility I’m sure some plants are capable of flowering on a 16/8 schedule very unlikely but seems to be the case here. This is just an assumption I am not an experienced grower.

Post some pics Growmie :love_you_gesture:

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I would change to 18/6.

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Update on this issue.

I turned the lights on 24/7 for a week to try and stop the plant flowering. It stopped growing and developed nice and dense stems that looked like they were still flowering.

After a week I reduced the light to 23 hours a day and dropped it to 22 hours today.

The plant that flowered is just starting to grow again but it’s not happy.
The other plant in the room is a party girl that stayed up all night and is now about 5 foot tall. Both plants were the same size when I started this post and one has grown about 2 feet (maybe a bit more). The other has only grown a few inches.

The picture showing 1 plant is the one flowering, or hopefully no longer flowering.

Second picture is the 2 plants next to each other. The flower girl is on the left while Ms Party all night is on the right. I have to keep moving the lights up because of her.

I was going to scrog them but Ms Party all night has strong branches and I don’t want to snap them because they never survive when I do it.

My two issues now are:

  1. Has Ms Flower with 16 hours of light stopped flowering?

  2. Do I prune Ms Party all night or break branches and tie her down?
    I don’t really want a pile of cuttings right now but would like to scrog the plant.