Thanks for the veggie hints. I also have another part of my garden
that needs a something...as will be explained below.

Our backyard backs up to protected wetlands (created as detention for
the subdivision), which are surrounded by "wildflowers" (which include
lots of grasses and not so decorative, invasive things such as
thistles). One corner of the back property line also has the
electrical transformer, the cable box and telephone box.

I have some stepping stone right at the property line, and then a
perennial border, which tries to carry on the prairie theme in a
relatively low-maintenance way. I've got assorted daylilies, yellow
yarrow, monarda, rudbeckia Goldsturm, purple coneflower, liatris, and a
few other things, all in a purple/yellow color scheme. There's also an
alder and a hazelnut included in the border, since they were there
already.

Right in front of the transformer, I planted a couple of Joe Pye weed,
hoping that it would get big and hide the transformer. However, not
only has it not really taken off in 3 years, it also doesn't really get
going until relatively late in the season, so I have to do a ton of
weeding around it. I'm thinking of tearing it out and putting in
something that would require less weeding (especially since that's the
hardest corner for me to access, so it usually gets put off until I
can't stand it any longer)

I'm trying to think of a good shrub that would carry on the prairie
sort of feeling, but haven't come up with any good ideas. I'm in Zone
5, and it's a relatively sunny site with clayey soil.

Thoughts?