correct photoperiod for starting indoors

[ramse]

I have just sprouted some seeds, with the intention of transplanting them outdoors in mid-May.
In mid-May there will be more or less 15 hours of light. So I set a photoperiod of 15/9 - 16/8.
well, now in a blog of a seed bank I read that if you move plants (from seed, not clones) from mid-May onwards, you can safely use a photoperiod of 18/6.
I always thought that if they move outside before June (solstice),
a photoperiod equal to that present in nature should be used.
Calculating the civil twilight, I could use a 16/8... more hours, I think it's risky
what do you think?

 

[Koondense]

I always used a similar schedule to end may/early june when transplant usually occurs, so 16/8 for me. But never vegged for more than 4 weeks from sprouting before going outdoors.

Cheers

 

[ramse]

But never vegged for more than 4 weeks from sprouting before going outdoors.

Cheers

my plants when they come out they will have almost 2 months of age (7 weeks from the emergency).
So almost certainly they will be sexually mature.
I can anticipate the transplant by a week... more is difficult for me.

however if I set a photoperiod equal to the natural one, regardless of sexual maturity, I don't think there are problems... what do you think?

 

['Boogieman']

I transplant June 1st, my daylight hours are 15hours 10 seconds daylight on June 1st where I live. Indoors I use 15/9. I try to keep it as similar as possible. I don't think the extra hour will make a difference honestly.

 

[ramse]

I transplant June 1st, my daylight hours are 15hours 10 seconds daylight on June 1st where I live. Indoors I use 15/9. I try to keep it as similar as possible. I don't think the extra hour will make a difference honestly.

yes, in fact an extra hour won't make a big difference...
in which month were they sown?
are they sexually mature when you move them?

thanks for sharing

 

[Mr. Greengenes]

Two important things are; your latitude and the genetics you're growing.

If you're fairly far north, you'll have a longer day in the summer. If you're as far south as me (Los Angeles, CA), you're longest day is not even 16 hours at june 21 (summer solstice). Longer day growers may have some leeway, but there's always danger of premature flowering if your veg time doesn't closely match the daylength.

So much cannabis has been bred indoors under very long days that there is a lot of genetics out there that don't veg happily at 16 hours or less. Other triggers, like restricted roots can accelerate flowering as well, so be sure to repot plants that will be set outside frequently, so that they will veg up nice and big.


Here in SoCal, I need to match my veg period EXACTLY to my summer day, and wait 'till mid june for some strains. Others, I can put out earlier, but still need to match the day.

 

[ramse]

Here in SoCal, I need to match my veg period EXACTLY to my summer day, and wait 'till mid june for some strains. Others, I can put out earlier, but still need to match the day.

thanks for the good advices

as I was saying, in mid-May I will have 15 hours of light, 16 counting the twilight
or always used a photoperiod of 16/8 (equal to the natural one) and I never had any problems, but I did vegetate them indoors only 15/20 days... (I always talk about seed plants)

in setting the photoperiod do you take into account the twilight time?

 

[troutman]

Use the same photoperiod the plants will experience outdoors and you'll have less problems.

 

[Mr. Greengenes]

https://www.timeanddate.com/sun/

This might be useful.

 

[popta]

They don't care about small things like that. Every indoor grow ever switched them straight from 18/6 to 12/12 and nothing unhealthy happened. Switching them from 18/6 indoors to 16/8 outdoors isn't going to trigger flowering or do anything weird and they'll probably be bigger and stronger going out if you prepared them under 18/6.

People do way weirder stuff than that to them all the time and they don't mind, like giving them a 30 hour day to switch what time the lights come on. Not a problem at all. They're building up/breaking down hormone levels that take WEEKS change. They don't care about single hours.

 

[ramse]

Switching them from 18/6 indoors to 16/8 outdoors isn't going to trigger flowering or do anything weird and they'll probably be bigger and stronger going out if you prepared them under 18/6.

at my latitude in mid-May from dawn to sunset almost 15 hours pass

a young seed plant will probably continue to vegetate... a clone or a mature plant, passing from 18 to 15... very likely it will trigger

moving out of the solstice onwards is inevitably ok.

 

[Mr. Greengenes]

16/8 outdoors

According to the daylength calculator, it shows 15:54:08 hours daylight in Olympia, WA on June 21. Where in the US is there a 16 hour day?

 

[gladysvjubb]

I have a 24 hour light cabinet. I start my seeds in there on a botanical heating mat. Then I transplant to a 6" standard pot (green). After they get to be 3-4 weeks old I move them from the 24 hour cabinet to the 12/12 room under my LEDS. Let the flowering begin!

 

[Sativan]

I grow my seedlings using accessible light. I only use indoor lighting if it's overcast outside.
When I move it outdoors it should match natural light very closely.

 

[Ace Rothstein]

I have just sprouted some seeds, with the intention of transplanting them outdoors in mid-May.
In mid-May there will be more or less 15 hours of light. So I set a photoperiod of 15/9 - 16/8.
well, now in a blog of a seed bank I read that if you move plants (from seed, not clones) from mid-May onwards, you can safely use a photoperiod of 18/6.
I always thought that if they move outside before June (solstice),
a photoperiod equal to that present in nature should be used.
Calculating the civil twilight, I could use a 16/8... more hours, I think it's risky
what do you think?

Why not start them outdoors now? in a sheltered area.
I started a bunch of seeds on April 15. I'm giving them increasingly longer direct sun as they grow.