The Rogerson Clematis Collection, the most comprehensive gathering of the genus clematis in the United States, has recently been granted National Collection status by the Plant Collections Network. Located at Luscher Farm in West Linn, OR, the Rogerson Collection has amassed over 800 species and cultivars of clematis, including a recent gift from Poland of rare and previously unavailable cultivars from the late clematis breeder Brother Stefan Franczak. The Plant Collections Network is a group of botanical gardens and arboreta working to coordinate a continent-wide approach to plant germplasm preservation, promoting education and high standards of plant collections management.
The Rogerson Clematis Garden also houses 456 genera of companion plants, represented by 870 species within those genera. The Rogerson Clematis Collection has inherited a horticultural research library, which will have a grand opening in April, 2019. They also have a clematis species seed bank, available for research and conservation purposes.