Are there ways to speed up (or shorten) the flower time of an outdoor plant?

Humanrob

Well-Known Member
This is my first outdoor. Where I currently live we have unpredictable Octobers, that can include high winds and hail or ice. I'd like my plants to finish up in September. The obvious first call is to choose strains with short flower times. Beyond that, anyone know any tricks?

I don't have issues with yield, I'm growing for a single patient and only need about 17.5 ounces to take her through a whole year and can have up to six plants -- so that would be about 3 ounces each from 6 plants, not a lot to hope for when flowering outdoors.

One thing I was thinking of doing was vegging indoors under 24/0 lighting for 6-8 weeks, ending in the third week in July. If I put them outside then, daylight is around 14 hours a day, and I would think that shift would cause them to go into flower... no? If that shift from 24 hours of light to 14 got them started flowering that early, then I'm pretty sure they'd finish before the end of September. Yes, they'd be "small", but a LOT bigger than if I grew them in my small/weak indoor setup (a clue: my indoor is all CFLs).

Another question while I'm here: do larger more mature plants take longer to finish flowering in general, then smaller younger plants? I know its initiated by daylight, but I'm wondering if the energy (and therefore time) necessary to push a 7' plant that is 4 months old into mature flowers, would take longer than a 4' plant that is 2 months old...

Thanks for your thoughts --

P.S. I don't have the logistics to be home twice a day in 12 hour intervals to cover and uncover them, so I can't use light deprivation.
 
Well the only hard and fast way I know to induce flowering would be light deprivation. Cover your plants every night 1-2 hours before sunset. Uncover them 1-2 hours after sunrise. That will force flowering. You can stop covering them altogether in september. And they should be done before october. You only have 6 plants so i suggest building a greenhouse. That will protect them from the elements (you can flower longer) and it will be easy to throw a light proof tarp over a greenhouse.

Another method that i've heard of, but cannot confirm, is pot size. According to some anecdotes on the web if you keep your pots extremely small this will induce bigger and faster flowers. Some strains will actually autoflower in midsummer. Others will just switch over to the flowering stage faster once 12/12 hits and ripen faster overall. I'm going to test the pot size method out this season. I'll report back with my findings.

For your needs I would suggest you get a fast flowering strain and make yourself a small greenhouse. Forget the light deprivation/small pots. That way you'll be able to have a decent yield, protect your plants from the elements, and also harvest fairly early in the season.
 

Humanrob

Well-Known Member
Well the only hard and fast way I know to induce flowering would be light deprivation. Cover your plants every night 1-2 hours before sunset. Uncover them 1-2 hours after sunrise. That will force flowering. You can stop covering them altogether in september. And they should be done before october. You only have 6 plants so i suggest building a greenhouse. That will protect them from the elements (you can flower longer) and it will be easy to throw a light proof tarp over a greenhouse.

Another method that i've heard of, but cannot confirm, is pot size. According to some anecdotes on the web if you keep your pots extremely small this will induce bigger and faster flowers. Some strains will actually autoflower in midsummer. Others will just switch over to the flowering stage faster once 12/12 hits and ripen faster overall. I'm going to test the pot size method out this season. I'll report back with my findings.

For your needs I would suggest you get a fast flowering strain and make yourself a small greenhouse. Forget the light deprivation/small pots. That way you'll be able to have a decent yield, protect your plants from the elements, and also harvest fairly early in the season.
Yeah, covering is the most guaranteed way -- easy enough to do if I can be home every evening at 7pm to cover them and every morning at 7am to uncover them. Every day. It doesn't look like that's an option for me this year, even just for July and August.

I have a small (5' x 8') home-made structure that will be completed to be a greenhouse-like thing. This year it'll be put to the test, and like everything else, the next one will be better. It's very sturdy and looks interesting in the garden, we'll see how it works.
 

churchhaze

Well-Known Member
It might be possible to speed up the outdoor season using 730nm pulses. Instead of putting a box over the plant for 2 hours before sunset and after sunrise, you can setup a timer so the 730nm comes on for a few minutes during sunset. It's not too hard or expensive to make a DIY 730nm array these days.

IMAG0181.jpgIMAG0182.jpg

Figured I'd point it out as a possibility only because this is in the advanced section. It's not a technique currently used in conventional practice.

Here's a commercial version of a 730nm flower initiator, but you could put together something better for cheaper DIY. It has an explanation of the theory, although it's more of an ad so take the explanations with a grain of salt.

http://growlightsource.com/the-flower-initiator-10-watt-ip65-indoor-outdoor-grow-light/the-flower-initiator-accelerator-far-red-730nm/

"
Outdoors:

Get your Short Day crop in earlier! Use the an online service to determine the Sunset and Sunrise for your location, a few days before your night reaches 10 hours in length, begin using the Flower-Initiator. Set your timer to turn the light on about 5 minutes prior to the indicated Sunset, set it to shut the light off about 5 minutes after total dark, perhaps for a total period of 30 minutes, as your sense of lighting suggests, and over time as your experience dictates for your location. You might want to adjust the timer to decrease the night's length to the optimum for flower development, for your specie, then lengthening the night further to fully finish flowers, if needed. This has been tested and proven accurate to push forward outdoor flowering forward at least one month. Next summer a test will be done to determine if this is appicable two months in advace. As the days shorten, readjust your timer settings to comply with your local Sunset, or keep it fixed at the current length if you like the productivity. Article by Ed Rosenthal."
 
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Humanrob

Well-Known Member
It might be possible to speed up the outdoor season using 730nm pulses...
That is interesting, no doubt.

I'm starting to think that if there were a way to do what I want to do, it would be common knowledge by now. It seems to be an ongoing quest for lots of folks who live in areas with short growing seasons. I'm still planning on experimenting with planting late after an extended indoor 24/0 veg, but I think I'll push it August and basically finish outside instead of inside. I have a lot of flexibility because huge yields are not necessary for me.
 

calicocalyx

Well-Known Member
What you could do is get them into 15 or 20 gallons pots and outside by early june. Let them harden off and veg under the sun, then bring them inside and flower for a couple weeks before bringing back outside. This will give them a head start into flowering and still make use of the sun (which will give you much more vigorous plants than the CFL's). It can take a week to harden off especially in the summer, may as well do that early on and it will be less stress later. 25 gallon pots and bigger are a pain in the ass to move around which is why I suggest 15 -20.
 

Humanrob

Well-Known Member
What you could do is get them into 15 or 20 gallons pots and outside by early june. Let them harden off and veg under the sun, then bring them inside and flower for a couple weeks before bringing back outside. This will give them a head start into flowering and still make use of the sun (which will give you much more vigorous plants than the CFL's). It can take a week to harden off especially in the summer, may as well do that early on and it will be less stress later. 25 gallon pots and bigger are a pain in the ass to move around which is why I suggest 15 -20.
Very interesting idea! Have you, by any chance, tried this? I'm not opposed to experimenting with the theoretical, just like to know what I'm working with. ;)
 

calicocalyx

Well-Known Member
I haven't tried this per se, but it'll work. If you haven't yet, take your plants and start slowly giving them direct sun ( an hour at first, then increase an hour each day), you'll see your plants grow a lot faster. Throwing them straight from 24/0 lights to outside probably will trigger them to flower, it's a question of if they stay in flower or be in this weird re veg state and you lose out on growing time (either flower or veg). Also this will be somewhat stressful, which is why I suggest getting them hardened off earlier. You also don't want to enter flower with any issues going on (potentially burning the plants from not properly hardening them off). Timing and the strain you are using are big factors and unfortunately largely unknown. Worth a shot, and if they are in pots you possibly have the option of moving them inside if they do go longer, although I wouldn't finish them under CFL's unless it's for a couple days.

To answer your original question, I have seen plants that were slightly rootbound finish earlier than the same strain in a bigger pot. Also plants getting a couple less hours of direct sun be a week or so ahead of the others. Even the north side of a plant can be a week earlier than the rest, simply less sunlight.
 

calicocalyx

Well-Known Member
Well the only hard and fast way I know to induce flowering would be light deprivation. Cover your plants every night 1-2 hours before sunset. Uncover them 1-2 hours after sunrise. That will force flowering. You can stop covering them altogether in september. And they should be done before october. You only have 6 plants so i suggest building a greenhouse. That will protect them from the elements (you can flower longer) and it will be easy to throw a light proof tarp over a greenhouse.

Another method that i've heard of, but cannot confirm, is pot size. According to some anecdotes on the web if you keep your pots extremely small this will induce bigger and faster flowers. Some strains will actually autoflower in midsummer. Others will just switch over to the flowering stage faster once 12/12 hits and ripen faster overall. I'm going to test the pot size method out this season. I'll report back with my findings.

For your needs I would suggest you get a fast flowering strain and make yourself a small greenhouse. Forget the light deprivation/small pots. That way you'll be able to have a decent yield, protect your plants from the elements, and also harvest fairly early in the season.

I have done my share of light deps, and know what entails greenhouse growing. I'm going low tech-ish. PVC hoophouse ( high sides, passive ventilation) with T5, then outside, t posts and pvc covers (high side for airflow, only cover if rain comes, no more than 2 days) for each plant at the end. All strains finish from beginning of september to end of september. Keep it simple-ish. 300 gallon pots tho. :)
 

Humanrob

Well-Known Member
What you could do is get them into 15 or 20 gallons pots and outside by early june. Let them harden off and veg under the sun, then bring them inside and flower for a couple weeks before bringing back outside. This will give them a head start into flowering and still make use of the sun (which will give you much more vigorous plants than the CFL's). It can take a week to harden off especially in the summer, may as well do that early on and it will be less stress later. 25 gallon pots and bigger are a pain in the ass to move around which is why I suggest 15 -20.
I'm totally new to "hardening off" plants. While I get the concept, I did not realize that you could harden them early in the season, and this would still hold if they were brought back inside, and then returned to outside. Just to be sure I'm understanding, the second time around they would not need to be placed in the shade at all, in order to adjust?

The 25 gallon pots is an interesting idea, I was planning on putting all of my outdoor plants into very large containers, or straight into the ground (with completely amended soil).

I have done my share of light deps, and know what entails greenhouse growing. I'm going low tech-ish. PVC hoophouse ( high sides, passive ventilation) with T5, then outside, t posts and pvc covers (high side for airflow, only cover if rain comes, no more than 2 days) for each plant at the end. All strains finish from beginning of september to end of september. Keep it simple-ish. 300 gallon pots tho. :)
Right now I have a micro-hoop house, sort of a light mobile cold frame, for starting two of my girls outside early (shooting for 4/20 if the weather holds out, apparently a popular time to start in Oregon). I'm also working on a small designated low-tech greenhouse, for two that will be planted a few weeks later. I would have the structural capability to do light deprivation... just not the lifestyle.

And 300 gallons is a swimming pool, not a pot! I have a pair of 100 gallon smart pots for the two going into the greenhouse (they will be partially submerged into the ground, mostly because I have height restrictions), and I thought those were huge! I've gotten mixed messages about whether the roots will breach the pot walls, but either way I'll be set up for it.

Oh, and the strains I picked up are: GSC Dough, WiFi OG, Alien OG, and Chem 91. I think the White Fire and the Chemdawg are going out first. By the way... what does OG stand for?
 

calicocalyx

Well-Known Member
You may have to harden the plants off a second time, but it's unlikely. Just go slow and you'll be fine, I've put them in dappled light, but I prefer to just slowly increase the direct light in order to have an idea about were they are in the process. Also if you go the route that I suggested, then they won't really fill those pots out so it would be more or less a waste of dirt/space as they would have already gone through the stretch process and wouldn't be vegging. 100 gallon pots with your starts put out in june could give you some decent size plants (8ft x 8ft), so think about your fence height and start training early on to be short and wide.
 

Humanrob

Well-Known Member
You may have to harden the plants off a second time, but it's unlikely. Just go slow and you'll be fine, I've put them in dappled light, but I prefer to just slowly increase the direct light in order to have an idea about were they are in the process. Also if you go the route that I suggested, then they won't really fill those pots out so it would be more or less a waste of dirt/space as they would have already gone through the stretch process and wouldn't be vegging. 100 gallon pots with your starts put out in june could give you some decent size plants (8ft x 8ft), so think about your fence height and start training early on to be short and wide.
Thanks for elaborating.

The ones going into the 100 gallon pots are going to be in an outdoor scrog, I'm hoping that and a lot of training will keep them under six feet. That's part of the "low tech greenhouse" I mentioned before, its a 5' x 10' structure I'm building that has an area around the perimeter to attach a scrog to. Each plant will only have approximately a 5(W)x5(L)x6(H) space, but I'm hoping to sort of spiral them under the screen, that worked with my indoor. This will definitely be a learning experience. I'm also hoping that by enclosing it in plastic I'll trap enough heat that I can put them out mid-May, but I'll have to see what things look like when I get there.
 

calicocalyx

Well-Known Member
They can easily double in size during flower, so do what you can to keep em below 3 ft throughout june and july. Mine are going into a similar hoophouse in early may. Pretty much mid 40's is about the lower temp limit that I'm comfortable with. Have fun learning and growing I'm sure you'll be commenting all along the way about what you'll do different next year. :)
 

ruby fruit

Well-Known Member
Well the only hard and fast way I know to induce flowering would be light deprivation. Cover your plants every night 1-2 hours before sunset. Uncover them 1-2 hours after sunrise. That will force flowering. You can stop covering them altogether in september. And they should be done before october. You only have 6 plants so i suggest building a greenhouse. That will protect them from the elements (you can flower longer) and it will be easy to throw a light proof tarp over a greenhouse.

Another method that i've heard of, but cannot confirm, is pot size. According to some anecdotes on the web if you keep your pots extremely small this will induce bigger and faster flowers. Some strains will actually autoflower in midsummer. Others will just switch over to the flowering stage faster once 12/12 hits and ripen faster overall. I'm going to test the pot size method out this season. I'll report back with my findings.

For your needs I would suggest you get a fast flowering strain and make yourself a small greenhouse. Forget the light deprivation/small pots. That way you'll be able to have a decent yield, protect your plants from the elements, and also harvest fairly early in the season.
Cant they just be covered couple hrs before the sun goes down then when it is night time uncover them again that night ?? Saves uncovering in the morning and then the plants dont sweat overnight in hot conditions ....
@tmb
 
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