Mineral deposits in our water can gradually build up and create a clogged showerhead which render the showerhead much less effective.
One natural solution is take the showerhead off, and soak in a pot of vinegar, for at least 6 hours. Heat the vinegar to the boiling point, remove from the stove and then let sit for those 6 hours. There is acid in vinegar and it should get rid of the mineral deposits in the showerhead.
Now put the showerhead back and it should be virtually as good as new.