Randia aculeata Ranunculus repens
Ratibida columnifera Ratibida pinnata
Rhamnus carolinianus Rhamnus crocea
Rhapidophyllum hystrix Rhizophora mangle
Rhododendron alabamense Rhododendron arborescens
Rhododendron atlanticum Rhododendron austrinum
Rhododendron calendulaceum Rhododendron camtschaticum
Rhododendron canescens Rhododendron catawbiense
Rhododendron catawbiense 'A. Bedford' Rhododendron catawbiense 'Album'
Rhododendron catawbiense 'America' Rhododendron catawbiense 'Baden Baden'
Rhododendron catawbiense 'Blue Ensign' Rhododendron catawbiense 'Blue Peter'
Rhododendron catawbiense 'Boursault' Rhododendron catawbiense 'Cheer'
Rhododendron catawbiense 'Dora Amateis' Rhododendron catawbiense 'English Roseum'
Rhododendron catawbiense 'Furnival's Daughter' Rhododendron catawbiense 'Grandiflorum'
Rhododendron catawbiense 'Ignatius Sargent' Rhododendron catawbiense 'Janet Blair'
Rhododendron catawbiense 'Jean Marie de Montaque' Rhododendron catawbiense 'Lee's Dark Purple'
Rhododendron catawbiense 'Mary Belle' Rhododendron catawbiense 'Nova Zembla'
Rhododendron catawbiense 'Purple Lace' Rhododendron catawbiense 'Roseum Elegans'
Rhododendron catawbiense 'Unique' Rhododendron catawbiense 'Vivacious'
Rhododendron catawbiense 'Vulcan's Flame' Rhododendron maximum
Rhododendron maximum 'Golden Lights' Rhododendron maximum 'Great Laurel'
Rhododendron maximum 'Mandrin Lights' Rhododendron minus
Rhododendron periclymenoides Rhododendron prunifolium
Rhododendron viscosum Rhus aromatica
Rhus aromatica 'Green Globe' Rhus aromatica 'Gro-low'
Rhus copallina Rhus copallina var. latifolia
Rhus copallina var. latifolia 'Morton (Prairie Flame™)' Rhus glabra
Rhus integrifolia Rhus ovata
Rhus trilobata Rhus typhina
Rhus typhina 'Bailtiger (Tiger Eyes®)' Rhus typhina 'Lanciniata'
Ribes aureum Ribes aureum var. gracillimum
Ribes sanguineum 'Brocklebankii' Ribes sanguineum 'King Edward VII'
Ribes sanguineum 'Pokie Pink' Ribes speciosum
Ribes viburnifolium Robinia hispida
Robinia neomexicana Robinia pseudoacacia
Robinia pseudoacacia 'Aurea' Robinia pseudoacacia 'Frisia'
Robinia pseudoacacia 'Purple Robe' Robinia pseudoacacia 'Tortuosa'
Romneya coulteri Romneya coulteri var. trichocalyx
Rosa californica Rosa virginiana
Roystonea borinquena Roystonea elata
Roystonea hispaniolana Roystonea princeps
Roystonea regia Roystonea spp.