The source of the Romanche with his Alpine Roses. Rhododendron ferrugineum (sometimes called alpenrose, snow-rose, or rusty-leaved alpenrose) is an evergreen shrub that grows just above the treeline in the Alps, Pyrenees, Jura and northern Apennines, on acid soils. It may grow up to 1 m tall and produces clusters of pinkish-red, bell-shaped flowers throughout the summer. The undersides of the leaves are covered in rust-brown spots, which give the species its scientific name.