From my experience the blocks take a long time to work. The key is to get the mineral mixed with the dirt asap. Using blocks it takes much longer for the rain to dissolve them. Use the mineral in a bag and mix it in the dirt and you will see much better results. Also as mentioned before, not much use putting any out from Oct to Dec, at least in my territory. This is a much cheaper way of bringing them in compared to attractants with pictures of big bucks on em.