Rhodiola rosea
Roseroot
Rhododendron cinnibarinum
Rhododendron ferrugineum
Alpenrose
Rhododendron lindleyi
Rhododendron loderi
Rhododendron ponticum
Rhododendron
Rhododendron racemosum
Rhododendron (racemosum)
Rhynchospora alba
White Beak-sedge
Rhynchospora fusca
Brown Beak-sedge
Ribes nigrum
Black Currant
Ribes rubrum
Red Currant
Ribes sanguineum
Flowering Currant
Ribes uva-crispa
Gooseberry
Riccia beyrichiana
Purple Crystalwort
Riccia fluitans
Floating crystalwort
Riccia nigrella
Black Crystalwort
Riccia subbifurca
Least Crystalwort
Ricinus communis
Castor-oil-plant
Rivini humilis
Bloodberry
Robinia pseudoacacia
False-acacia
Romulea columnae
Sand Crocus
Rorippa islandica
Northern Yellow-cress
Rorippa palustris
Marsh Yellow-cress
Rorippa sylvestris
Creeping Yellow-cress