Changing to 12:12

Can someone please explain how to tell if a fem plant is ready to be switched from veg phase to flower phase?

A photo and your strain type would greatly help.
But it’s all about your tent or room and timeframe. A general rule is 4-5 weeks without problem. If it’s a Sativa and it’s 2 feet she could double in height on the stretch. So if you had a 6’ ceiling that would be good. Have you done any training or topped it? How many branches does it have how wide is it? How many do you have and how big is your space?
I say wait as long as you can and be patient. The bigger the veg the more you get in flower.


It’s best to wait until you see fully developed pre-flowers


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I don’t believe all strains will show when they are ready with pre-flowers. Also I don’t believe there is a need to wait for full maturity before flipping. Some plants would get just to big if you waited. You need to manage your space and height appropriately.


I agree with @WickedAle. Most of my plants have showed preflowers but not all.

Generally speaking if you are happy with the plants size after 1 month you can flip. Most strains are mature enough at this point, in my opinion.


Agree with others. 4 weeks veg is usually considered the minimum amount of time to switch.
I personally flip when I have the growth I was looking for which always seems to be more than 4 weeks.


Ye I agree with the lads at the top it’s all about space you have because you could veg as long as you want to gain the desired size rule of thumb I use is if it’s the size of your arm from your elbow to the end of your hand it’s time to flip to 12/12 anyone else ever used that scale

No never thought of that. I use a SCROG net so I veg until it looks filled. :slight_smile:

If your outside let it grow otherwise be very careful not to end up growing too long and having your colas burned in your lighting. Space is truly a commodity

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