It would be nice if you could get more of the reddish material that is going in a quarter circle shape . it looks great with other brick & the stones. I love that & would try to continue if you could find some more. Maybe put an ad in paper for whatever it is called. I like the natural look & the reddish color really "pops". Your edging is durable & will last forever! Glass breaks & baby food jars are pretty small & would sink or get inside moisture & not look good too long. China plates on edge would get knocked over & are too delicate with your wide leaved Hostas & other plants. Perhaps if you know where a lake is with driftwood, some of that would look good maybe not as edging but laid around in garden bed area. I think it is really shaping up nicely! Great job!! Jan

I'd stay away from glass also. Check on Craigslist for your area, often this type of product is listed for free. I just typed in "broken bricks" for our area and came up with several listings. My son gave away broken pieces of concrete to whomever would come get it. I made a pathway to my outhouse out of it. There's lots of free stuff to be had out there! Also check freecycle.org for your area. I'd spray the gravel with Round Up to get rid of the weeds. Keep repeating now and then if you see any tiny green pop up. You'll eventually get rid of them all. It's fun to see progress, isn't it?
Arlene

A simple edging of twigs would work well there. You can also do a weave called "wattle" with straight twigs. It doesn't have to be twigs if you want a GJ look, use salvaged wire or similar material.

Here is a link that might be useful: Willow edging

Thanks for the feedback.
@Sunnyca those are actually thin bricks. A local architectural salvage store had a free day with selected items. I couldn't get there until my lunch hour so the free section was mostly empty, but they did have some bricks left. I think you and @luvs2click are right about the glass. I didn't think about breaking and everything else. I've been all over CL and Freecycle hunting down broken bricks and patio tear outs. Love the soft orange bricks but those are harder to find, but they have such a nice color. @rock_oak_deer thanks for the link. Got me thinking in a new direction. Maybe not that exactly but I could definitely go in that direction.
Has anybody ever seen tin cans used as edging?

Well I used a large pumpkin can with top & bottom out of it over the sprinkler turn-on at church as it is down in ground & kept disappearing! It doesn't last all that long. So I don't think I would use tin cans, also can get nasty cut & infections from rusty tin. Jan

Something metal would be nice but make sure its not pointy. Some of the low garden fences I've seen with pointy spear like tops give me the willies.
Looks liek the area is shaping up nicely!
Kathy

this is off the wall but have seen it , anyway do you like oysters??? buy the biggest ones you can find have a b-b-q and use the shells for the edging. geeme