'Rosi Klose' Bergenia Rosilla
Rosinweed: perfoliatum 'Rosish One' Carnation: Dianthus
Rosularia 'Rosy Cushion' Rose
'Rosy Tips' White Bottlebrush 'Rosylva' Forget-me-not
'Rotblum' Heartleaf Bergenia 'Rote Glocke' Pasque Flower
'Rothschildiana' Glory Lily 'Rotstrahlbusch' Switch Grass
'Rotunda' Chinese Holly 'Rotundatum Cristatum' English Hedge Fern
'Rotundifolia' Flowering Ash 'Rotundifolia' Japanese Holly
'Rotundifolium' Doublefile Viburnum: plicatum 'Rotundiloba' Sweetgum
Rough Bluegrass Rough Cocklebur
Rough Honey Myrtle Rough Horsetail
Rough Seeded California Poppy Rough-Leaved Goldenrod 'Fireworks'
Rough-Stalk Bluegrass Roughstem Goldenrod 'Fireworks'
Round Head Bush Clover Round Headed Leek
Round Leaf Birch Round Leaf Chastetree (spp.)
Round Leaf Chastetree 'Wild Korea' Round Leaf Holly
Round Leaf Navel Wort Round Leaf Tea Tree
Round Leaf Vitex (spp.) Round Leaf Vitex 'Wild Korea'
Round Lobed Hepatica Round-fruited Banksia
Roundleaf Buffaloberry Round-leaf Fan Palm
Roundleaf Greenbrier Round-leaf Hawthorn
Roundleaf Holly Osmanthus Roundleaf Livistona
Roundleaf Oregano Rowe Ceanothus 'Gerda Isenberg'
Roxburgh Fig Royal Agave
'Royal Aspirations' English Larkspur 'Royal Burgundy' Bromeliad: hybrid
'Royal Burgundy' Oriental Cherry 'Royal Cape' Cape Leadwort
'Royal Crown' Magnolia 'Royal Dwarf' Sheep Laurel
Royal Fern (spp.) Royal Fern 'Purpurescens'
Royal Fern: regalis spectabilis Royal Mallow (spp.)
Royal Mallow 'Novella' 'Royal Mix' Garden Pea
Royal Palm Royal Palm: spp.
Royal Paulownia Royal Poinciana
Royal Purple Autumn Sage Royal Purple Brunfelsia (spp.)
Royal Purple Brunfelsia 'Macrantha' 'Royal Purple' Lilyturf
'Royal Purple' Smoke Tree 'Royal Red' Norway Maple
'Royal Robe' Germander 'Royal Robe' Wood Sage
'Royal Standard' Common Torch Lily: Kniphofia 'Royal Standard' Hosta
'Royal Star' Star Magnolia 'Royal Wedding' Oriental Poppy
'Royal White' Eastern Redbud 'Royalty' Crapemyrtle: indica
'Royalty' Hungarian Lilac 'Royle' Japanese Maple
'RozaleaŽ Coral Pink' Azalea 'RozaleaŽ Light Lavender' Azalea
'Rozanne' Hybrid Geranium 'Rozannie' Aucuba