Why is the “flip” different indoors than outdoors?

[okmtnbiker]

Just some musings from an insomniac. I grew a couple cabinet crops after we became legal, I followed all the rules and sure enough after I flipped to 12/12 in just a few days there were pre-flowers. This year is my first stab at outdoor. I have my legal 6 girls, all different strains (mostly sativa). I have an app that shows hours of daylight. When my last girl finally got pre-flowers we still had 14:20 of daylight. I was told even a pinhole of light would stop flowering indoors after the flip. To add to this, mostly for a test, I kept an outside light on my garden shed turned on 24/7. Waaaaay more than a pinhole of light. So my girls all flowered before we got to 14 hours 20 minutes of daylight plus a fairly bright lamp about 10’ away on all day and night. Explain this please.

 

[okmtnbiker]

I still can’t sleep so here ya go. The pictures are from July 17 that is the LAST plant that flowered.

 

[Wastei]

I still can’t sleep so here ya go. The pictures are from July 17 that is the LAST plant that flowered.
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Not really news but there's always variations between how many hours a phenotype need to show desired traits in veg. Some veg fine under 18 hours while some may need 2 hours more to stay fully in veg.

Genetic variations.

 

[okmtnbiker]

Two strains are the same as the indoor strains, plus how do you explain my outside light? How do you explain the full moon? Both very much more than a pinhole of light, right? I weren’t shooting for news but discussion.

 

[hotrodharley]

How do you explain street lights? I think it’s the intensity of the light after lights out as well as colors if they’re affected.
My first winter back in Alaska I had no tent. Flowered a boatload of plants in my 1 room cabin. I watched movies on a television set. Read using a red headlight. No hermies. Colas as big as donkey dicks. Neighbor used to come over just to stare at them. In the meantime I’d turn my kitchen light on to make tea or whatever.

 

[Bukvičák]

I still can’t sleep so here ya go. The pictures are from July 17 that is the LAST plant that flowered.
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Growing indoor you are losing 2 hours of darkness for phytochrome transition. 12/12 is actually 12/10… This wont happen outdoor where your 14/10 is actually 14/10. Flowering is determined by lenght of darkness not lenght of light…

 

[okmtnbiker]

Huh?

 

[Flowki]

It seems to me the worse situation is high lights off temps in the 80's for leaf temps, a strong enough light leek in a usable spectrum to trigger stomata, and low RH to allow higher respiration rates. Everything is there to trigger day time respiration + veg triggers, while blocking night respiration and flower season trigger, as the grow lights come back on. Mid to late in flower, I think that will become more and more of a risk. The plants are not growing for yield, they are growing for the process of making seeds, one way or the other. If they are tricked into thinking it's the start of season, then dropping seeds makes sense, to get a start on the next generation.

Or the 24/7 veg type environment triggers some kind of evolotionary survival instinct. They didn't evolve in that kind of situation, and I think they may realise they could not survive in that situation due to the increased necessity on the day/night respiration cycle during flower, so they drop seeds as a last resort.

 

[Lucky Luke]

Because we have a switch we can flip..

 

[Merlin1147]

@Bukvičák is right. At sunset outside the spectrum shifts toward far red 720-740nm this caused the phytochromes in the plant to go from the active Pfr isoform to the inactive or sleep Pr isoform. Basically it transitions the plant to nighttime mode within minutes rather than hours. Inside I use far red light 5 minute before and after lights out. I run 12/12 in bloom and use the far red primarily to reduce the weeks to maturity. A friend of mine uses far red and runs 13.5/10.5. He feels he’s getting better production with more daylight.

 

[Merlin1147]

Flowering is determined by lenght of darkness not lenght of light…

Not necessarily. I once ran a trial using a 28 hour light/dark cycle instead of 24 hour. So at the end of the week I’d have 6 full cycles instead of 7 and by using a 16/12 schedule there were 12 more hours of daylight per week. You can do the math. My thinking was more daylight more production. Yeah, another rabbit hole, it didn’t work out that way. Even though they were getting 12 hours of dark, they never transitioned to bloom. After 5 weeks I changed then to 12/12 and they flowered normally.

 

[ComputerSaysNo]

Inside I use far red light 5 minute before and after lights out.

So this is 10 minutes of red light around the flip.

What kind of light do you use? Or is it an adjustable LED where you can change the spectrum?

When my last girl finally got pre-flowers we still had 14:20 of daylight. I was told even a pinhole of light would stop flowering indoors after the flip. To add to this, mostly for a test, I kept an outside light on my garden shed turned on 24/7. Waaaaay more than a pinhole of light. So my girls all flowered before we got to 14 hours 20 minutes of daylight plus a fairly bright lamp about 10’ away on all day and night. Explain this please.

Around 14:30 hours of daylight is normal for the outdoors "flip" for most plants.
I have 1 plant outside, and it pretty much to the day started to flower when day length crossed this threshold.

With regards to the external light, others have responded already. It depends a lot on the spectrum of the light, and probably also on a lot of other environmental factors, and possibly also plant genetics. I also think what Bukvicak said is very important: the transition to flower mode is much more natural and appropriate for the plant outdoors, that probably makes it less sensitive to external light sources.

The moon light should play absolutely no role, the plants have evolved over millions of years to flower under moon light. It's also very weak light.

BTW for day length calculations and much more, here's a great website: https://www.timeanddate.com/sun/

 

[Merlin1147]

What kind of light do you use? Or is it an adjustable LED where you can change the spectrum?

I have diodes from rapid led that are in a separate driver and timer
And yes they come on 5 minutes before the main lights go off and stay on for 5 minutes after they go off. So 10 minutes total.
That schedule is for during the initial flip so there is not too much red to encourage stretch. Once they are fully in bloom the far reds come on with the main light but they stay on 5 minutes after the main goes off. So 12 hours 5 minutes total

 

[ComputerSaysNo]

That schedule is for during the initial flip so there is not too much red to encourage stretch.

Will your timing encourage or discourage stretch? Not clear from how you worded it.

Also, do you think an infrared lamp would work as well? I'm talking about those lamps that are used in kitchens to keep plates warm, or for relaxation.

You said 720-740 nm, is this the sweet spot, or could it be close to that and work as well?

 

[Merlin1147]

Will your timing encourage or discourage stretch? Not clear from how you worded it.

Also, do you think an infrared lamp would work as well? I'm talking about those lamps that are used in kitchens to keep plates warm, or for relaxation.

You said 720-740 nm, is this the sweet spot, or could it be close to that and work as well?

Red light will encourage stretching. So I tend towards more blue light during that period especially with sativas. Some times it works and other times the plant just wants to go up. 720-740 is the sweet spot. IDK about the IR heat lamps for this purpose. You can get what some call an “initiator puck” which is far red.

 

[okmtnbiker]

Very interesting guys keep it going I swore I would quit before I grew indoors again but I’m starting to have second thoughts. No way your indoor girls are as happy as my outdoor but yours are prettier than mine too loo.

 

[decrepit digits]

Light leaks do not cause flowering plants to revege, for me light leaks do not cause herme's either, I can run floros off to the side with no ill affect, plants seem to focus on light straight above them. Never have flowered at 12 12 always at 14 10 to know if they will make it outside. Flowering is triggered by decreasing light or increasing darkness incrementally outside it is minuets per day. Not talking tropic's thats a different game.

 

[DCcan]

These

Will your timing encourage or discourage stretch? Not clear from how you worded it.

Also, do you think an infrared lamp would work as well? I'm talking about those lamps that are used in kitchens to keep plates warm, or for relaxation.

You said 720-740 nm, is this the sweet spot, or could it be close to that and work as well?

Bud Booster Emerson Effect Sun Board 48 LED Strip 660nm 730nm IR Quantum Grow | eBay

HAS 36 OF THE 660nm Deep Red and 12 OF THE 730nm Far Red(IR) LEDs per strip. They actually work best with a constant current driver. If you don't know how to wire them, just ask. If you look around, you can even find ways to set them up on regular old full size cookie sheets.

www.ebay.com

Look into Emerson's work in PS1 and PS2 signaling, the amount of red/ far red plays a part in shade avoidance, growth, etc.

 

[okmtnbiker]

Amazing how much you guys know keep it up I’m learning!

 

[ComputerSaysNo]

Bud Booster Emerson Effect Sun Board 48 LED Strip 660nm 730nm IR Quantum Grow | eBay

HAS 36 OF THE 660nm Deep Red and 12 OF THE 730nm Far Red(IR) LEDs per strip. They actually work best with a constant current driver. If you don't know how to wire them, just ask. If you look around, you can even find ways to set them up on regular old full size cookie sheets.

www.ebay.com

Look into Emerson's work in PS1 and PS2 signaling, the amount of red/ far red plays a part in shade avoidance, growth, etc.

This might be easier than making them myself from LED boards and drivers.
Thanks a lot!