Mary,

The Russian Sage and Ratibida pinnata can present challenges in cold winter areas. This is due to the exposed roots may be more prone to winter kill. Also, excessive fertilizing with too much nitrogen can compromise flower production with leggy growth. Most important though ,is to determine  the soil's nutrient content. See attached link for a soil test

https://www.canr.msu.edu/news/soil-testing-returns-through-msu-extension

After you have the results of your soil test, you can amend the soil if needed. Also, I would add additional mulch to the roots of your plants for winter coverage.

Thanks for Asking Extension