I know I'm just butting in here, since I can't answer for Janice. Is your
sister in an apartment? Some apartment complexes have community gardens. She
could try Boise State University, there are garden plots there. They go to
residents of the apartments first, but if there are some left over, to
anybody who applies. I believe the fee is $5 for a water key. I think when
you give the key back, you get your fee back. So, it's more of a deposit. I
haven't seen any other community gardens around here. But I used to live in
the university apartments, so I know how that works.

More info on BSU garden plots:
Applications are taken in the apartment office on the top floor of the admin
building.
If she gets a plot, she will need to amend the soil as much as she can.
People have been growing things here for years without amending and have run
the soil down. She will have to till or turn the soil herself. The
university does not have anybody do this for you. Some of the plots haven't
been used for years and are overgrown (maybe 8 feet high) with weeds. There
is a very good chance of getting one or even two plots, since I've never
seen them all in use.

Off topic:
Yes, I know BSU is a funny abbreviation for a university. One person I told
that I attended BSU did not believe me and thought I was making it up. It
really exists. They really use that acronym. And it does not stand for Bull
Sh*t University.