Yep, check the gardening section in the hardware store. But, also check the tools, plumbing and electrical sections. Those isles also have unique hangers that might work for you.
If you can find a piece of plastic pipe, or hose, of the correct size, you could cut off rings, split the rings on one side and drive a screw through the other side. Or, just tack several laces onto a board and tie the probes on with the laces.
I am with you; cable management is an issue - a real pain in the neck. I just don't have any space to hang them. I ended up just winding them up, putting several of the same type in a Ziplock bag, writing information on the bags and seating the bags, vertically, in an open top box. It consumes a large spot on my bench, which I am not happy about, but at least I can find what I need and I am avoiding disasters.