Would sawdust work? Possibly discourage the weeds? I have never tried this but I am planning my gardens with accessibility in mind. My DH is on and off with his back and I want to make sure that he has access to the entire yard. I eventually want to use concrete screenings in the pathways but cannot afford that now.

Sawdust isn't that great.I have pine sawdust in my blueberry patch and it just clumps up and makes the wheeling thru a lot harder.Where the sawdust is packed down due to age it isn't that bad.Though weeds do grow thru the old and newer sawdust.
At this moment I'm thinking of just growing grass in my isles as I slowly convert by garden to raised beds.

put down newspaper it works great