Experimentation is great. ... My solution was to develop a set of DOF equations and use them to program a programmable calculator which lives in my camera bag. So when I encounter a situation that requires special attention to achieving sharp focus on critical elements in the scene I can enter the data into the calculator and get an answer in the blink of an eye. It works great! ....Or you can just set your lens to f/8 and have fun shooting. Most of your landscape pictures will probably turn out just fine.
It might be daunting to some to program their own equations (at least it seems that way to me). But it is definitely a fine way to go if you can do that, otherwise, if you have a smart phone (whether android based or apple's) there are lots of free DOF calculator programs/apps available out there to do the same thing.
f/8 and be there is also a wonderful time tested method.