Fleur de Lawn from Pro Time Seed in Portland would be a great option...
https://ptlawnseed.com/products/fleur-de-lawn 

Thank you, Alec. The Fleur lawn looks like it will meet my needs.  Although yarrow grows higher than 5 inches, so not sure how that will work in this mix.

However.... Looks like we are moving into the house in early October. Will the lawn/meadow seed grow quickly enough so we won't have a muddy back yard all winter?  

If not, I am thinking to have a border area of sod laid down along the patio edges, and the rest of the small yard seeded. That way we'll have a grassy area for our 12 pound dog. If we do this, will the seeded area eventually overgrow the sod? (a good thing, in my mind!)

Will this idea work?

thank you!
-Beth Monticue

   

The mixture will need a about 14 days to germinate and establish.  The turf boarder way be a good idea.  

The mixture will have to be mowed once a week. The yarrow, as well clover and grass will become quite tall if not mowed. 

Alec