I feel people often confuse "defoliation" with simple pruning.
The idea behind defoliating is removing large fan leaves to allow the buds on the bottom to get more light, however this is foolish for a few reasons. For one, the fan leaves being removed is akin to removing solar panels from your house and being surprised your batteries aren't fully charging anymore. For two, most of those buds not getting enough light should have been pruned off in the first place. I mean, the expression "low hanging fruit" exists for a reason.
"Defoliating" won't make your small buds any larger, it'll only restrict the growth of your large buds.
Learning how to properly manage and maintain a canopy will yield far greater results than defoliation ever will. Why defoliate when your canopy is perfectly even and flush?
Some people take like the bottom 1/3 off, like my buddy does. What do you think of these? Granted I was neglectful earlier at the beginning of this grow, my fault.
Personally, I am one of those people. I keep the bottom 1/3 of every plant completely bare and clean, from start until around week 3-4 of flower I continue to prune until the bottom 1/3 is bare.
The bottom 1/3 of a plant is always useless. The only thing the bottom of the plant serves is to be a habitat for pests and diseases alike. Simply keeping up on pruning your plants (any plant) will drastically reduce your chances of both pests and diseases. No place for pests to hide, and more airflow being blown through the plant.
Sure, indoors we may not need to prune as aggressively, as we're able to control both the airflow, temps, and humidity.
Outdoors? Not so much. In the low desert, I have both low humidity and low airflow. I prune a little more aggressively to compensate for this outdoors. Pics below are from a few weeks ago, you can see the leaves at the bases of the plants from the recent pruning. They've been outside since mid-June and they made it through the 110-130F summer like champs. If I didn't keep up with pruning, the bugs and heat would have absolutely destroyed these plants.
You can see just how bare it is at the bottoms of all my plants. Nothing good comes from the bottom of the plant, and failure to prune the bottoms of the plants can lead to issues in some cases. Stuff beneath the canopy saps resources from the actual canopy itself, and those tiny nugs underneath the canopy are usually the ones that like to throw out bananas. They don't get enough light, so in some cases they throw out bananas.
The only use the stuff on the bottom 1/3 of a plant has is for cloning
I usually try to take some lowers that definitely will die off like a week before flip. Touch up some more day or two after flip, and finish no more than a week or so after flip.
In your shoes, I'd be removing everything on the bottom 1/3 of those plants. The bottom 1/3 of those plants of yours are not only serving no purpose, but are taking resources from the canopy of your plants. Guarantee that your canopy will grow much more if you prune the crap on the bottoms. Regards.
tl;dr: Don't defoliate, only prune.
