Light control 20/4

I want to keep my lights on for 20 and off for four. I’ve tried going back and shifting the schedule. It wont let me do more than 12/12.
Why cant i control my own grow from the boxes I paid for?
Your generic recipes dont allow me to customize the way I want :frowning:


Grobo tries hard to keep the growing process as simple as possible and have only applied the light timing cycles that are scientifically proven to be the MOST beneficial. They have a system that keeps you on the rails which is great for some and frustrating for others. If you are looking for full control, a tent is the way to go. I grow in a tent as well as my Grobo so I can play with every element of the grow.


If you go to shift schedule can’t you go back to Veg by clicking on “Previous”? At that point you should be 18/6

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@Wake - Can’t use a tent. I’m in a wheelchair and usage of only 1 hand. The Grobo (I own 2 of them) is perfect for me except for the software / lack of being able to customize a generic Indica recipe in this case.

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@Mpower11 - I tried going back to Stage 1 and Stage 2. Both stages only allow 12/12 Now. I was able to go to previous stage 2 from stage 3 and it only allowed 20/4 one time. Both Stage 1 & 2 were 20/4 when the grow was started (Generic Indica). It changed to 12/12 when going to stage 3. As of now, I’m changing the 12/12 on/off time DAILY to get the 20/4 schedule I want.



This is a photo plant correct?

May I ask why you want to change to 20/4? Your in full flower already… Your going to mess up the hormones of the plant by changing to 20/4? Maybe if I understand I can help you more…

By changing back to Stage 2 you should be back on 20/4… I would send a email to support they have the power to get you back on Stage 2…

Like I said before I wouldn’t at this point

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on a side note I would remove all the big fan leafs blocking the light


I had this same thing, you have to submit a ticket for the. To push a fix to get back to the non-flower lighting schedule.


Hey @TheWarden,

You may want to upgrade your firmware too, new release went out this week that fixes a shift stage bug we discovered.

I’m with @Mpower11, why do you want to go back to veg when you are so far into flower? I’d finish this grow and try to adjust the next instead of pushing this one back. Just my 2cents. :wink:



Thank you @Wake @Mpower11 @Stephen

Firmware updated on both Grobos
Will remove big fan leaves light blockers
Only going back to veg to hack the light to 20/4 but that only worked once.
Thank goodness for Grobo Journals!

It’s an AutoFlower 80% Indica (Mephisto Double Grape) according to the provider who grew this with 20/4 until harvest, netting 4oz and 7oz on 2 diff grows (see pics). Granted it’s soil. Said anything less than 20/4 would produce light airy buds and low yield.

Still a n00b (7 grows) trying to learn all I can. Getting confused with different suggestions. :crazy_face: :thinking: :face_with_raised_eyebrow:
Thanks everyone for their expertise and input! :grin:


The first thing we need to confirm is are you growing a Photo or Auto??

In flower with a Photo you want to be on 12/12 lighting

If it’s a auto you want to be 18 or 20 hours per day the whole grow…

Let’s confirm this before you do anything else… (trimming included)

Note: The recipe your running is a Photo Recipe

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I get what you’re trying to do. The dosing might be off between late veg and flower but here’s my thought…end your current grow, start a new grow with the same recipe, move forward to late veg and then just extend it multiple weeks from the get go. This will keep you in the 20/4 light cycle until she’s ready for harvest. This way you won’t have to worry about missing the change in schedule.


Its Auto.

Did not know the Generic Indica recipe I picked was Photo

@FireGuy Should I end the grow, pick the Generic Hybrid Auto Flower (bottom left of pic) and advance to late veg and extend?

Thankks @Mpower11 & @FireGuy !


The reason I recommended the photo recipe and stay in late veg is because of the light schedule. If you want 20/4 with an auto recipe you will have to manually change your times every day (been there done that, it’s a pain in the ass!). The nute dosing could be off but I have no idea on that. Totally up to you how you want to go about it. Autos are always 18/6 where photos are 20/4 until transition.


I think if it was me I would let support adjust your recipe for you to a auto recipe generic (you are correct with a A in the corner). I just don’t want to see a mistake happen to your girl.

I would include pictures of your plant.

I’m not the best person for training Autos in Grobo. Most people don’t top. Some people tuck there leafs vs cutting them off

Reason is you don’t want to stunt the growth of auto plants. (Shock or Stress it out)

Or like @FireGuy said you can adjust yourself also. Up to you