Rick wrote:
I want to start a multi year project, where year one is is get rid of
the nettles, year 2 is to do the landscaping and do the grass, and
then year 3 is to think about plants. I don't want my new grass filled
with nettles that I burried during landscaping.

Can I put a weedkiller down that kills nettles & roots ? Right now I
don't care if it kills everything, as long as I can grow stuff next
year I am fine.

Chuck Roundup at it if you really want, BUT if you just grass it
and keep mowing the nettles will die off quite quickly.