For the longest time i keep getting these rust spots that gradually turn the leaves yellow and drop. It happens between the 4-6 wk of bud,sometimes worse and sometimes not so bad. Buds turn out good, but just doesnt seem right. I grow in 5g warrior pots with promix hp ph@ 5.5-5.9 using the flora nova lineup feeding at every other watering and adding a little calmag during watering cycle. The room is well ventilated and circulated @81* and 40%rh (lights on) and 68* and 44 % rh (lights off) this is really starting to bother me. Ive been told before that this is considered natural die-off of the plant, but most gardens ive seen stay a little lusher a bit longer than these. At this point any help would be greatly appreciated, thanks.
Are you growing in soil or something else like coco?
They look like that could use some calmag and some nitrogen as well... Looks like your plants have just finished the stretching, they use up heaps of nitro during this period.