Autoflower light cycle

Ogkushen

Member
I have been running autos in the light cycle 18 / 6 in a dwc system, they are now in flower, do i continue with the light cycle or do i switch to 12/12?
 

TheDifferenceX

Well-Known Member
As mentioned above, you don't need 12/12 for autos. Most would not recommend 18/6 either.

If you have lower temps, maybe stay at 24/0. If you struggle with high temps, use 20/4 and pick the 4 hours where your room would get the hottest and have lights off during that time.
 

Wattzzup

Well-Known Member
If you struggle with high temps, use 20/4 and pick the 4 hours where your room would get the hottest and have lights off during that time.
This

Plus unless you have some weird circumstances I would give the plant some rest even if it’s 2 hours.
 
With Autoflowers you typically run the same light schedule through the whole cycle. I usually go with 18/6 to let the plant feed the microbes in the dark phase but with dwc you could do 20/4 or even 24/0. Just make sure you don't exceed the DLI. Too much light will stress your plant, decrease yield and increase the chance of getting into trouble.
 

Ogkushen

Member
With Autoflowers you typically run the same light schedule through the whole cycle. I usually go with 18/6 to let the plant feed the microbes in the dark phase but with dwc you could do 20/4 or even 24/0. Just make sure you don't exceed the DLI. Too much light will stress your plant, decrease yield and increase the chance of getting into trouble.
DLI , what does that mean? Yeah my leaves been pointing upwards almost the whole time, i guess that is a sign of light stress, yield is pretty low, but atleast i learn, managed to fight root rot and it's my first dwc :)
 
DLI is daily light integral and is the amount of light a plant can handle in 24h in its current stage. PPFD is the light intensity a plant can handle in its current stage.

PPFD Seedlings: 150 - 300 umols
PPFD Vegetative: 300 - 600 umols
PPFD Flowering: 600+ mols

So depeding how many umols you throw at your plant multiplied by the hours per day you get your dli. This might come in handy to do the math:


So lets say you are throwing 200 umols at a seedling for 18h a day that gives you an DLI of about 13. What the max dli per grow stage is depends on a lot of factors like strain, temperature, humidity, how much water a plant gets, co2 concentration in the grow area. You can find research papers on the net to give you some ideas.

For me in my grow environment seedlings do great at a dli of 10-15. vegetative does best at about 20 and in flower the max they can handle is 35 before showing sings of stress. These numbers may apply to your environment to some degree for seedling and vegetative stage but might go higher in flower.
 
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