I recently had to turn off the chat feature on my website; https://growingweedindoors.org because I was being asked one question every day over and over: Why Are My Marijuana Plants Flowering Early and How Can I Revert Them Back to Vegetative?
First a long story short; female cannabis plants start to flower when they detect less light unless they are plants grown from auto flower seeds.
So I always ask, “Are you sure you didn’t purchase auto flower seeds”?
If they are not auto flowers then the female plants detected less light and started flowering. Since it’s the beginning of summer how could the plants detect less light? This is a great question with an easy answer if you take a moment to think about it.
If you’re starting your plants indoors to get a jump on the outdoor season your plants are getting 18 to 24 hours of artificial light each day. After a month indoors, your plants expect that same amount of light each day which keeps them in the vegetative cycle.
When the plants are moved outdoors, it doesn’t matter if you have a typical housing situation with trees, fences, buildings etc partially blocking sunlight or they are in a wide open field. There is a very good chance those plants will start to flower because they are looking for their usual 18-24 hours of light and they’re only getting about 15, and that’s if they’re lucky.
If you move your indoor plants outside and they start to flower early just let them be. They will flower for about 3-4 weeks, get used to the new light and revert back to the veg cycle all on their own. This will cost you 4-6 weeks or more of grow time.
What I mean is your plants won’t grow much when they are recovering from the stress brought on by inconsistent light timings. The plants won’t be perfect and they may turn into a hermaphroditic plant and I don’t recommend doing this. Another long story short; there isn’t much THC in a hermaphroditic weed plant even though I am smoking hermed buds right now that are 18 months old and I do get a buzz, usually only in the morning. In the evening not so much so think about the next suggestion.
Another option is to add light outside to make up what’s missing. The plants should then be grown normally under the sun and extra light until they start to flower again. This does stress your plants and will most likely add to your growing time. You’ll lose the 14 days reversion time plus more as the plant recovers from the stress it’s been placed under.
If you had little buds started you’ll see weird looking single leaves growing out of them when the reversion commences. You can leave them or pick them off. DO NOT cut off the little buds that are forming.
IMO the best way to handle premature flowering is moving the plants back indoors giving them 24 hrs of light. They’ll revert faster and resume growing in the vegetative cycle. Warning; if you bring them back out with the same light conditions after they revert, they will herm again. I think it’s best just to finish the grow indoors but if you’re dead set on bringing them back out after they revert you’ll have to set them up for success.
First start with 24 hours of light to induce the reversion process for two days. Reduce the light to 20 hours for two days then down to 18 hours. Our goal is to keep the plants in the veg cycle with indoor light down to 15 or 16 hours each day. After two days on 18 change to 15 hours and watch them closely for 7 days. This brings us to a total 11 days of reversion indoors. If they continue reverting you can bring them outdoors and hopefully they will stay in the veg cycle until they start to flower naturally.
If you notice they are flowering again your only choice is to grow them indoors, Go 24 hours of light for a couple of days then switch to your regular schedule; I now use 20 hours on during the veg cycle. As you can see growing outdoors is not as easy as it seems; especially in the mid-west. Besides bugs and critters, early flowering is a pain and is why I prefer to grow indoors.
If you have this problem right now and you can’t move them back indoors, you must add light to your plants outdoors to enable them to revert back to the vegetative cycle. If they were grown indoors under 18-24 hours of light I would suggest you add enough light to your plants so they have at least a solid 18 hours of light and it has to be good light. It doesn’t have to be as intensive as the sun or indoor grow lights but it can’t be just one bulb.
In the future if you plan on starting your plants indoors than moving them outdoors during the veg cycle, you must run your lights only 14-15 hours per day. This will keep your seedlings growing indoors in the veg cycle and they won’t start to flower when you move them outside. If your area has more or less hours of light during the growing season then adjust your indoor timings appropriately. One thing you must realize: all of this is strain dependent so make sure you read about the strain you’re trying to grow.
I would love to hear what you think about this article and your experience. Be sure and leave comments below. I check all the time and will respond or answer questions ASAP.
Visit my website at https://growingweedindoors.org/ for more tips from a grower with 38 years’ experience.