Have 24 x 5 area between garden home no sun no grass all mud. Gravel?

Put landscape fabric down first, then 2" - 3" of gravel. Maybe add a few stepping stones to walk through the area easier.

Have your thought about putting colored rock in the space?

Have our thought about using colored rock?

Yes, Level ground, Lay porous membrane (weed suppressant) and then add gravel or Pea shingle. You could also add a few stepping stone slabs as a path.................

My best bet would be cement.

Sounds like the makings of a great patio type project. Depending upon the layout you could pour a slab/tile/pavers next to an exiting door and do a combo of filler (rock, gravel, tiles, pavers) to cut the cost and add interest.