From what I've heard yes it is good during flowering. Its sappose to increase resin production, also fattening the buds up a bit. From what I've heard you use Blackstrap molasses, or Grandmas molasses found at Safeway, Alberston's, ect. I think its 1 table spoon to a gallon and can be used all the way to harvest date. Again, this is what I've read, never used it, but will try soon.