Wich is the Transition-Point of Lightdeprivation, around 1st August?

[romanoweed]

When am i done with deprivating ,

and i can let Autumn doo the Rest?

I grow 18 Weeker Sativas , 45 Degree northern Hemmisphere , middle Europe

 

[romanoweed]

2nd Question:

Do my Plants need Ventillation to survive?
Cause once i did an Automatic deprivation , and after i went back from Holiday a week later i found every Plant dead!!!
I still dont know the Reason. only Guess: they could have grown too fast and touched the Sunheated Top, therefore rotted?

 

[St. Phatty]

@42 North Lat

about 1st of August.

 

[Amynamous]

@42 North Lat

about 1st of August.

Just curious if there’s a chart or formula available?

 

[troutman]

Answers:

Question:1 If you grow 18 week Sativas, they'll need less than 13 hours of light to keep them flowering.

Question 2: Without air circulation most things die.

There are weather websites where you can check daylight hours in your area.

 

[romanoweed]

Is there a electricityless Method to achieve sufficient Aircirculation? This is insane i will do this Guerilla. Any help is so much apprechiated . If i fail, there will be no 70s Vietnamese from my Side to share on Overgrow or else.
I mean the pure 70s Vietnamese, not the the Vieblack

Thanks for all the help!!!!!
thanx @ troutman