depends on what u mean by trim-
iif U mean supercropping, then yes
or topping, then yes
or pruning branches/leaves that wont get much light, then maybe..thats ur call
or pruning bottom branches to help air circulation, then yes
if U are trimming back bcuz they're getting too bushy, then definitely not...trimming is never the answer unless u are 10-20 days away form harvest., not only can that cause enormous amounts of stress to the plant, but if U have nutrients in the soil the roots may end up sucking out too much food than the foliage above need, and whatever u left on the plant may get burned..trust me I know from experience (
Grow Journal #2 - post #123 "Today I cut off more than 50% of my leaves!")
U can see off to the right of my hand the plant in the bucket and whats left on it.
the next day every single one of my budsites was burned!~
i had to cut back so many leaves on my plants.I was devastated.
Lesson:always tuck or train before U trim. Thats one of the few things that u can do to the plant that cant be undone.
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