California poppy Eschscholzia californica
Canadian dwarf cornel Cornus canadensis
Canadian serviceberry Amelanchier canadensis
Canary marguerite Argyranthemum frutescens
Canterbury Bells Campanula medium
Carnation Dianthus caryophyllus
(1)
Castor oil plant Ricinus communis
Catnip Nepeta cataria
Chamomile Matricaria recutita
Chard Beta vulgaris
Cheddar pink Dianthus gratianopolitanus
(2)
Cherry Prunus cerasus
Cherry Prunus avium
Cherry plum Prunus cerasifera
Cherry-laurel Prunus laurocerasus
(1)
Chicory Cichorium intybus
China aster Callistephus chinensis
China fir Cunninghamia lanceolata
Chinese angelica tree Aralia chinensis
Chinese magnolia Magnolia sieboldii
Chinese Peony Paeonia lactiflora
(25)
Chinese snowball Viburnum macrocephalum
Chinese wisteria Wisteria sinensis
Chinese witch hazel Hamamelis mollis
Chives Allium schoenoprasum
(1)
Christmas rose Helleborus niger
Chrysanthemum Chrysanthemum
Cinnamon rose Rosa majalis
Clammy Locust Robinia viscosa
Clematis Clematis
(3)
Climbing hydrangea Hydrangea petiolaris
(3)
Clusius gentian Gentiana clusii
Coleus Plectranthus scutellarioides
Columbine Aquilegia
Common barberry Berberis vulgaris
Common Blue Violet Viola sororia
Common box Buxus sempervirens
(5)
Common Broom Chamaecytisus
Common Cotoneaster Cotoneaster integerrimus
Common cowslip Primula veris
Common elder Sambucus nigra
Common heather Calluna vulgaris
(263)
Common hop Humulus lupulus
Common Juniper Juniperus communis
(1)
Common laburnum Laburnum anagyroides
Common lilac Syringa vulgaris
(77)
Common Peony Paeonia officinalis
Common sage Salvia officinalis
(1)
Common snowberry Symphoricarpos
Common snowdrop Galanthus nivalis
Common walnut Juglans regia
Common yarrow Achillea millefolium
(5)
Coneflower Rudbeckia
Coral flower Heuchera
(190)
Coriander Coriandrum
Corkscrew willow Salix babylonica
Corn poppy Papaver rhoeas
Cornelian cherry Cornus mas
Cosmos Cosmos bipinnatus
Coville's phlox Phlox covillei
Cowberry Vaccinium vitis-idaea
Cranberry Vaccinium macrocarpon
Creeping Bellflower Campanula rapunculoides
Creeping jenny Lysimachia nummularia
(1)
Creeping juniper Juniperus horizontalis
(1)
Creeping Myrtle Vinca
Creeping Phlox Phlox subulata
(3)
Creeping zinnia Sanvitalia procumbens
Crimson Bottlebrush Callistemon citrinus
Crown Imperials Fritillaria imperialis
Cup and saucer vine Cobaea scandens
Curly-leafed Cabbage Brassica oleracea
Cushion spurge Euphorbia epithymoides
Cypress Spurge Euphorbia cyparissias