Those are great looking plants….you’re a natural!!
A 500w full spectrum is a good choice for a 4x4.
Those girls should really stretch once U flip them, so plan on that space to be wall to wall.
IMO lollipopping is the right move…..the last thing U want is a bunch of larfy loose buds that are not worth the pain it requires to trim them.
If you’re not gonna do a scrog net, I would consider training them a bit more by spreading them out & tying down the outer perimeter. Do this before the stretch and you’ll have 25, 30, or more tops and a yield that is much easier to work with.
I can’t use a scrog b/c of access, so I tto maximize the area of the canopy, in your case a 4x4, with as many tops as possible. U may not have 3 or 4 big giant donkey dick colas, but I’d rather have 3 dozen golf ball size tops. The giant colas are nice to look at but are more prone to mold…..
Anyway, spread em out, tie em down and those lower sites will grow up to form your canopy.
U can see in my pic that the canopy isn’t perfect but I’ve got a helluva lot of tops.
Good luck…..I’ve also included a chart that really shows exactly when a plant needs its primary nutrients. I used it early on as my grow guide. The one thing that many growers don’t realize is how much N a plant uses in those first few weeks of flower. I used to think that once the flowering began, the need for N was minimal……not the case.
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