How to force flowering?

I’m a first time grower and purchased Northern Lights feminized for migraine headaches and restless legs. It’s not auto flowering. They didn’t get enough sunlight, grew tall. Someone suggested I crop them which I did and they look good on top. We live in Minnesota and they need to flower, what do I cover them with and how long. I took pictures but not sure how to post them.

Why do you need them flower? And obviously because you want her to grow buds lol, but I’m asking because is there a specific reason why you’re trying to force flower?

Nature will do it for you if you just wait another month, but if you can’t wait then I’d suggest buying a tent-like-structure to place over your plant. Something that has lots of air flow, but keeps the plant in darkness. Another member @Clay0 just went through this and tried using trash cans, but they didn’t allow enough air flow and boxed the heat inside, almost killing them. Luckily he noticed before too much damage was done, and will be able to have a good harvest in a few months. So just something to keep in mind when trying to force flower.

Some member here said in Minnesota if they haven’t flowered by the end of July they won’t have enough time?

Hmm, I would suggest checking your local “farmers almanac” and checking to see when sunrise and sunset are 12 hours apart. Example, it might say on September 1st that sunrise is 7 am and sunset is 7 pm. That means this will be the beginning of flower for you outdoors.

Now, from that date, you’ll want to fast forward 8 weeks on the calendar. After 8 weeks check the date, and then check the estimated temperature. From there you’ll be able to judge if the plants will make it or not.

12 hour apart sun rise/sun set doesn’t happen until September 24th. Our 1st [predicted frost is October 3rd. Can I dig them out and put in buckets in house with grow lamp?

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Damn, now I see what you’re saying @Bobbi!

You could try that, but most likely you’re going to cut some roots when trying to transplant. I’m sure if you search the internet you might find someone who’s already done this (transplanted a plant from outdoors in soil to indoors) and can give you tips!

Your best bet would be to either buy or build a structure that can cover your plants from sunlight, but allow air flow while keeping the plants in complete darkness. You could honestly just buy a couple reflective tarps from Harbor Freight Tools for a few bucks, and buy some wooden stakes. Then just put the stakes in the ground and tie the tarps to each stake, making a roof and side walls. You could take it down easily and put it up at whatever hour you need to.

Just a quick brainstorm. I’m sure if you get creative you could come up with something really nice. I hope I helped!

Thank you, you’ve been very helpful. I’ll check into the reflective tarps. I do have a lawn chair cover that fits over the top nicely but the whole bottom is open. Think maybe I can use that and rigs something up to keep the light out but lets the plants breath. Thank you!

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I grew outside last year. No journal, bad memory…but it seems to me, my plants started flowering in August even though the Autumnal Equinox, the 12 hour day/night @ktreez420 referred to, is late September for me.
The few times I’ve grown outdoors over the decades, if I remember, the plants always started flowering a month before the equinoxes. Frost would still cause me to harvest early, even with the early start. Hopefully you’ll see signs of buds, or at least preflowers, soon.

Building an enclosure to block all light is your best bet to start it now.

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I think I’ll put my grow light on it first thing in the morning because it doesn’t get enough sunlight too, then cover it. 12 hours sun/ 12 hours covered?

Im in the mid west. My outdoor plant started to flower in July. But i planted before the last frost of my season but i germinate indoors April 1st and protect against frost a move to outdoors.

and this is her.

I have a lot to learn, next year I’ll know what I’m doing.

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The problem with not knowing is you don’t know what you don’t know.
The more you know the more you know you don’t know.


My outside plants started flower last week in TN.

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I’ve never grew inside before, but whenever I’ve grown outside, my plants have always been ready middle of October, around the just before frost. The whole 12/12 photo period shit messed with my head forever when I first started reading up on growing. Because I knew my plants always flowered well before there was less than 12hr 1min of daylight. Pretty sure the plants have a much better gauge of when to flower, in order to successfully produce viable seeds, or finish, for our purposes, than a setting on a timer.

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I’ve accepted the 12 hr rule as a tool for “tricking” plants to flower. I’m positive that there are early frosts that catch plants too soon. But I feel that if a plant is put outside early enough to mature and follow it’s genes, it will produce more often than not. I feel that people taking this and trying to do outside grows following inside grow schedules for amount of vegetative growth, then expect the plant to complete the flowering process with the limited time once there is a 12/12 daylight/night period naturally, is what has led to this crazy forcing flower idea.

If I were you, I’d just make sure the plants are well tended to, and wait and see what happens. Bet they finish OK unless you set them out late.

I can’t remember what date I put them out, first part of May. My problem was lack of sun, we are surrounded by woods on 3 sides and neighbors. They didn’t get enough sun! They grew tall and gangly, too late I cut them back because I am 1st time grower and didn’t know any better. I’m putting my grow light on them when they have no sun, covering them for the 12 hour black out. I’m wondering if I can use 100% cotton black fabric as a blackout? I sew and can make something out of that and they can breath.

I checked out the tarps, can they breath through these?

I have no experience whatsoever with this, but I would think the cotton would be better for the plants, but will it block the light. I just pulled my black tee-shirt over my head, and plenty of light filters through.