Lighting Schedule For Auto Flowers


When growing auto flowers, does one have to switch light schedules from 18/6 to 12/12? If so at what week do I do that? I’m in week 6 plus a few days. Cheers for any assistance.


you may keep autos on any light schedule. i usually give them at least 12 hours per day, but some growers use 12 hours per day from seed to harvest with no problem.i likento use 24/0 first two week, then 18/6 until flower starts then 12/12 until harvest.

Update: I’m considering changing this philosophy. My auto has been on 12/12 for more than a month and I just put her back on 24/0. Her already dank flowers have doubled in size… So idk


Thank you kindly basementstealth.


You can use the same light schedule as a photo plant. I wouldn’t go 24/0 the entire grow with the exception of the germination period because plants need a rest. You could ride 18/6 all the way out if you’re feeling saucy, but to focus on your actual question:
I count from germination day one and all of my Autos showed solid signs of making their flip around day 33. So I would have flipped to 12/12 at the beginning of week 5.


Thank you very much ElektricJack, I appreciate that.


I start my white widow with 18-6 time and never change it until harvest them


I am a new grower and I am growing white widow autoflower. growing inside and I am having a hard time getting my humidity past 45%


If you can get in contact with the seed producer, you could ask them. It’s best to follow their instructions. The company I went with suggested 18/6. I was doing 24/0 for over a month before I asked them and just recently switched to their recommended schedule. I can’t say if it’s the switch, or if it’s just the life cycle of the plant at 35 days, but I noticed a pretty large amount of new growth for my NYC Diesel plants after I went to 18/6


A coolmist humidifier at Walmart for 20.00 or thift store 5 bucks, where I got mine.


I have the same issue. I haven’t started growing yet, still prepping tent and purchasing supplies. Been running hydrometer and my humidity ranges from 25%-32%. So I have got a ways to go out here in the desert. Going to thrift store tomorrow to find one too, but be careful purchasing them at them used. Most people don’t properly clean out their humidifiers and there can be mold trapped inside of them. So thoroughly bleach inside containers and parts prior to using on your girls.


I don’t know anything anymore I just put my autos back under 24light and their buds are nearly doubling in size once or twice a week. I’m also a chemist with the food


what stage are they in? how do you know when the plants are in veg state or flowering? dumb question right…i am real new and am growing white widow auto in a closet. I think I am doing ok but I think I need some ventilation. any help for a budget?

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Small fan? Leave the door open?

Remind me. Is your goal to raise or lower humidity?


I really do not need to do either right now I 3do not know when to switch my lights from veg to flowering. I am very new and I got my seeds here. I planted 4white widow auto and now they are about 6inches tall. they look good but when do I switch? how close should I put the lights. I have a 900 watt phizon…not real greatbut…I am growing in a 2x6 foot closet that Is covered in mylar and I keep a humidifier going always but the is pretty wow in here. I do not know if my extension cord will carry a fan too.i could use all you can help with. I am in oklahoma


when I change from veg to flowering do I leave the veg light on with the flowering light or do I just have the flowering light on? should I begin 12 lights on and 12 lights off? this is autoflowering white widow.
since it has been 3 weeks I am going to switch to flowering in 1 week or so is that right? thanks so much I need so much help now I am grateful.


I’m assuming u have a blurple led with a veg and flower switch?


I have a viparspectra with both bloom and veg but mine I can adjust the levels, not just on or off. I set my veg at 100% and bloom at 25 to start out. When by autoflowers started blooming, I turned bloom up 100% and left my veg on at 100%:v:


Autos do their own thing under various lighting. My grow 12/12 from seed: