Han wrote:
[snip] We killed the lawn in front of our first home by covering with
newspaper. Worked just fine, and we got a very nice front garden.
The next owners of course promptly took all our nice plants out and
made it a lawn, but we had 18 years of a nice front flower garden.
No chemicals other than mulch.

I've seen people around here using cardboard held down with rocks or cinder
blocks. Looks like %&!#, but it works.

Depending on the size of the area, I'd just pull up the turf.

Jon