Darkest red to purple blooms are just shocking to the eye. It doesn't look real but the blooms are so rich in color this is a must have for your garden. Foliage changes in the fall and puts on a dark burgundy tint. This cultivar is a sport of the macrophylla Merveille and was given the name Merveille Sanguine. This variety is very, very sensitive to late spring frost so I've rated it a zone 7 but still, be careful in those areas where late spring frost can damage the ability to bloom. Found in France in 1939 by Henri Cayeux.