Parking

[Why Not Indeed]

a jobsworth coming along and telling him 'you can't plant that here...'

That's one benefit of planting a small native [eg hawthorne] that grows into something bigger - plausible deniability.
Having said that, are the council mowing it? Someone must be if it's remaining as a patch of grass.

 

[Bod ...]

Bod's already tried and failed to do something with that piece of ground. Planting anything may be subject to a jobsworth coming along and telling him 'you can't plant that here...'

That'd what happened. Yet they don't say nothing when idiots park on what used to be grass.

 

[Bod ...]

Landmines..

Tried them too.

 

[Bod ...]

That's one benefit of planting a small native [eg hawthorne] that grows into something bigger - plausible deniability.
Having said that, are the council mowing it? Someone must be if it's remaining as a patch of grass.

I've mowed it for the last 15 or so years

 

[Why Not Indeed]

I've mowed it for the last 15 or so years

Wellllll.....surely step 1 is to stop mowing it? Things will then start growing.
It's interesting that your local authority is actually well funded enough to send jobsworths around!