Keeping mice and rats out of storage sheds

I have little ground squirrels that look like chipmunks that get into everything!  Antelope squirrels.

I had to build a bunker garden.  Dug down two feet and surrounded it with metal siding.  They still dug under that!  So I dug out all of the garden dirt and put metal wire mesh under the entire thing.  Waiting to see how that works!

I have found that mice and chipmunks can't climb through lemon grass.  I think it is too sharp.  In Arizona lemon grass will survive and thrive in intense heat.  I am starting a lemon grass boundary around my larger garden area to see if this will deter them.

It is a constant battle!