What to do with this bit of land

[NotAGolf]

I hopped over the boundary fence at the end of my garden (on the left in the pic). I cleared it to stop the brambles growing through into my garden, but leaving it barren like this feels like a bit of waste. It's about 2m deep and ~12m long.

It backs onto a footpath, but the path is a further ~10m to the right in the pic, and down a steep hill covered in brambles, so no one apart from my immediate neighbours can see it. It's not my land though, so I can't really build anything on it, and I wouldn't want to spend loads of money on it in case someone kicks off.

I was thinking of planting some wildflowers, or perhaps a little veg patch (or perhaps both), but there's a couple of problems:

1. The ground is terrible. It's covered in rubble (used to be a railway line) so it's not exactly great soil for planting.
2. I feel like I might be fighting a losing battle keeping the brambles at bay if I don't put some kind of mesh/fence in.

Any suggestions?

 

[NotAGolf]

Yes, it's council owned land and it's a popular path, so I think the liklihood of grabbing the land and claiming it after 7/12 years is very unlikely.

The goal here wasn't to extend my boundary, just to turn an area of untended brambles into something a bit nicer.

If there's a risk of fines, then I'll just leave it alone and cut the brambles back when they cross the boundary.