Most of the time, a "big" f-number is recommended for landscape photography. But a high f-number such as f/16 or f/22, when dealing with APS-C or FF cameras, means a very narrow or small aperture. The large aperture is at the other end of the scale at f/1.4 or f/2. See What is aperture, and how does it affect my photographs?What is aperture, and how does it affect my photographs?