Echinocereus pacificus San Carlos, BCS
Echinocereus pacificus San Carlos, BCS is a fast growing claret cup cactus from the mountains of Baja Mexico. These plants have survived -2F but have not survived colder than that. These plants may have potential for colder climates if you can create a microclimate that it likes. These make nice potted plants and get awesome red flowers.
I do not guarantee these in a zone 4/5/6/7 because everyones growing conditions are different but this would be a good trial plant to grow in your cold outdoor garden. Try to plant outdoor 90 days before 1st hard freeze.