Hanging items on a block wall is really a great beginning handyman job. The hurdle is what to use to support the weight, and how to you get it into the block?
Normally, the things people hang on a block wall are somewhat heavy. I’ve seen a lot of Southwestern design items made of wrought iron that hang. They aren’t super heavy, but they aren’t like hanging a small picture either.
I like using masonry screws or tapcon screws for this. In using these, the job does become much like hanging a picture. Most of the outdoor items you will hang will have a point to hang them from or will have a hanger on the back.
Pick a spot on the wall and drill your hole. It is easier to drill into the block itself rather than the mortar in between the blocks. Also, the bit doesn’t tend to wander in the block like it would in the mortar.
Drill to a depth that is appropriate for the screw and then turn the screw into the hole. You obviously want to leave the head out enough so that the item can comfortably rest on it. You may also want to paint the head of the screw so that it blends in with the object you are hanging from it.