Echinocereus coccineus Kingman, AZ

Echinocereus coccineus from Kingman, AZ is the furthest west the species goes. These plants can have dark black spines but have very nice red flowers in early spring. Regardeless these plants can take some serious cold taking -22F in our garden without issue. Plants are generally more clumping than the Colorado forms.
 
I do not guarantee these in a zone 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.