Cercis

Cercis chinensis 'Avondale' (Avondale Chinese Redbud)
Cercis occidentalis (Western Redbud )
Cercis siliquastrum (Judus Tree )

Chaenomeles

Chaenomeles speciosa (Flowering Quince)

Chilopsis

Chilopsis linearis (Desert Willow )

Chimonanthus

Chimonanthus praecox (Fragrant Wintersweet)

Chionanthus

Chionanthus retusus (Chinese Fringetree)
Chionanthus virginicus (White Fringetree)

Chitalpa

Chitalpa tashkentensis 'Pink Dawn' (Pink Dawn Chitalpa)

Cladrastis

Cladrastis kentukea (American Yellowwood)

Clematis

Clematis (hybrid) (Hybrid Clematis)
Clematis montana var. rubens (Pink Anemone Clematis)
Clematis tangutica (Golden Clematis)
Clematis terniflora (Sweet Autumn Clematis, )
Clematis viticella (Italian Clematis)
Clematis viticella 'Huldine' (Huldine Italian Clematis )
Clematis viticella 'Polish Spirit' (Polish Spirit Italian Clematis)

Clerodendrum

Clerodendrum trichotomum (Harlequin Glorybower )
Clerodendrum trichotomum 'Stargazer' (Stargazer Harlequin Glorybower)

Clethra

Clethra alnifolia (Summersweet )
Clethra alnifolia 'Ruby Spice' (Ruby Spice Summersweet )

Cornus

Cornus 'Eddies White Wonder' (Eddie's White Wonder Dogwood)
Cornus Venus® (Venus Dogwood)
Cornus alba (Tatarian Dogwood )
Cornus alternifolia (Pagoda Dogwood)
Cornus amomum (Silky Dogwood)
Cornus canadensis (Bunchberry)
Cornus controversa (Giant Dogwood)
Cornus controversa 'June Snow' (June Snow Giant Dogwood)
Cornus drummondii (Rough-leaved Dogwood)
Cornus × elwinortonii Starlight® (Starlight Dogwood)
Cornus florida (Flowering Dogwood )
Cornus florida 'Golden Nugget' (Golden Nugget Dogwood)
Cornus florida 'Welchii' (Tricolor Dogwood )
Cornus kousa (Kousa Dogwood )
Cornus kousa 'Gold Star' (Gold Star Dogwood)
Cornus kousa 'Radiant Rose' (Radiant Rose Dogwood)
Cornus kousa Scarlet Fire® (Scarlet Fire Dogwood)
Cornus kousa 'Sunsplash' (Sunsplash Dogwood)
Cornus kousa 'Wolf Eyes' (Wolf Eyes Dogwood)
Cornus mas (Corneliancherry Dogwood)
Cornus officinalis (Japanese Cornelian Dogwood )
Cornus racemosa (Gray Dogwood )
Cornus × rutgersensis Celestial® (Celestial Dogwood)
Cornus sanguinea (Bloodtwig Dogwood)
Cornus sanguinea 'Midwinter Fire' (Midwinter Fire Dogwood)
Cornus sericea subsp. sericea (Redosier Dogwood)
Cornus sericea subsp. sericea 'Argenteo-marginata' (Variegated Dogwood )
Cornus sericea subsp. sericea 'Elegantissima' (Variegated Tatarian Dogwood )
Cornus sericea subsp. sericea 'Flaviramea' (Golden Twig Dogwood )
Cornus sericea subsp. sericea 'Hessei' (Siberian Dogwood )
Cornus sericea subsp. sericea Ivory Halo™ (Ivory Halo Dogwood )

Corylopsis

Corylopsis (Winterhazel)
Corylopsis pauciflora (Buttercup Winterhazel)
Corylopsis spicata (Spike Winterhazel)

Corylus

Corylus americana (American Hazel )
Corylus avellana (Hazelnut )
Corylus avellana 'Contorta' (Contorted Filbert )
Corylus avellana 'Red Dragon' (Red Dragon Hazelnut)
Corylus avellana 'Rote Zeller' (Rote Zeller Hazelnut)
Corylus colurna (Turkish Hazel)

Cotinus

Cotinus coggygria (Common Smoketree )
Cotinus coggygria Golden Spirit™ (Golden Spirit Smoketree)
Cotinus coggygria 'Royal Purple' (Royal Purple Smoketree)
Cotinus obovatus (American Smoketree )

Cotoneaster

Cotoneaster bullatus (Hollyberry Cotoneaster)
Cotoneaster divaricatus (Spreading Cotoneaster)
Cotoneaster horizontalis (Rockspray Cotoneaster )
Cotoneaster intergerrimus (European Cotoneaster)
Cotoneaster lucidus (Hedge Cotoneaster)
Cotoneaster multiflorus (Many-flowered Cotoneaster)
Cotoneaster simonsii (Simons Cotoneaster)

Crataegus

Crataegus 'Autumn Glory' (Autumn Glory Hawthorn)
Crataegus ambigua (Russian Hawthorn)
Crataegus crus-galli (Cockspur Hawthorn)
Crataegus germanica (Medlar)
Crataegus laevigata (English Hawthorn )
Crataegus laevigata Crimson Cloud™ (Crimson Cloud Hawthorn)
Crataegus laevigata 'Pauls Scarlet' (Paul's Scarlet Hawthorn)
Crataegus × lavallei (Lavalle Hawthorn)
Crataegus monogyna 'Flexuosa' (Contorted Singleseed Hawthorn)
Crataegus phaenopyrum (Washington Hawthorn)
Crataegus punctata (Dotted Hawthorn )
Crataegus viridis (Green Hawthorn,)
Crataegus viridis 'Winter King' (Winter King Hawthorn )

Cydonia

Cydonia oblonga (Quince)

Cytisus

Cytisus scoparius (Scotch Broom )
Cytisus scoparius 'Moonlight' (Moonlight Scotch Broom)

Daphne

Daphne × burkwoodii (Burkwood Daphne)
Daphne caucasica (Caucasian Daphne)
Daphne genkwa (Lilac Daphne)
Daphne mezereum (February Daphne )

Davidia

Davidia involucrata (Dove Tree )

Delonix

Delonix regia (Royal Poinciana)

Deutzia

Deutzia gracilis (Slender Deutzia)
Deutzia gracilis 'Nikko' (Nikko Slender Deutzia)
Deutzia × kalmiiflora (Kalmia Flowered Deutzia)
Deutzia × lemoinei (Lemoine Deutzia)
Deutzia paviflora var. amurensis (Amur Deutzia)
Deutzia scabra (Fuzzy Deutzia)