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Optimum intensity for preflower and early flower phase ?

Hi all . i m looking to find out what is the optimum light intensity for the early stages of flowering period for both kinds of cannabis. outside i dont worry about it but indoors i dont know where i should be . should i be full intensity by this time of the growth? i dont have a par meter so from your experience where do you think i should be regarding intensity ?

thanks

4 answers1 reply

Comments (5)

E_heroi

Apr 05, 2021

ok so the lights shouldn't be on max around that time right ? if we suppose that my light on 100% dim give 1000ppfd would it be correct to say that for the first 1-2 weeks of flower they should be at 75%? does the intensity in this period affect yield ? is it related to the stretch of the plant in the first weeks or is it purely genetics that define the stretch ? sorry for the many questions . this is a grey area for me as im coming from purely outdoors to indoor growing . now i respect the sun so much more.......lol

Mr. Grow It

Apr 05, 2021

Replying to

I would run it at 75% for the first few weeks then increase to 100%. Someone else might argue otherwise. If you give too might light it could actually hurt yield. That's called "light burn". Here's more info: https://www.mrgrowit.com/post/light-burn-light-stress-in-cannabis-plants

So IMO it's better to be a little under when it comes to the amount of PAR rather than over. Lots of people give their plants too much light and their plants end up suffering - especially with these newer LED grow lights.

Stretch is mostly genetics and of course the health of the plant. If the plant is over-watered and/or suffering from deficiencies then it won't stretch as much. Also, blue spectrum of light inhibits cell division so that can also impact the stretch. That's why some growers like a lot of blue light in Veg so the plant will have tighter node spacing.