Chamaenerion angustifolium
Chelidonium majus
Greater Celandine
Chenopodium album
Fat-hen
Chenopodium vulvaria
Stinking Goosefoot
Chloris barbata
Swollen Windmill-grass
Chromolaena odorata
Devil Weed
Chrysosplenium alternifolium
Alternate-leaved Golden-saxifrage
Chrysosplenium oppositifolium
Opposite-leaved Golden-saxifrage
Cichorium intybus
Chicory
Circaea alpina
Alpine Enchanter's-nightshade
Circaea x intermedia
Upland Enchanter's-nightshade
Cirsium arvense
Creeping Thistle
Cirsium dissectum
Meadow Thistle
Cirsium eriophorum
Woolly Thistle
Cirsium oleraceum
Cabbage Thistle
Cirsium palustre
Marsh Thistle
Cirsium vulgare
Spear Thistle
Cirsium x celakovskianum
Cissus verticillata
Princess Vine
Cladium mariscus
Great Fen-sedge
Claytonia perfoliata
Springbeauty
Cleome spinosa
Spiny Spiderflower
Clerodendron chinensis
Glory Bower
Clerodendron paniculatum
Pagoda Flower
Clerodendron quadriloculare
Starburst Bush
Clerodendron speciosissimum
Java Glory Bower
Clerodendron thompsoniae
Bleeding Glory-bower
Clinopodium ascendens
Common Calamint
Clinopodium vulgare
Wild Basil
Cochlearia officinalis agg
Common Scurvygrass
Cochlearia officinalis agg.
Scurvygrass
Coeloglossum viride
Frog Orchid
Coffea arabica
Coffee
Comarum palustre
Marsh Cinquefoil
Combretum indicum
Rangoon Creeper
Commersonia bartramia
Conium maculatum
Hemlock
Conocarpus lancifolius
Qalab
Conopodium majus
Pignut
Convallaria majalis
Lily-of-the-valley
Cornus capitata
Bentham's Dogwood
Corrigiola litoralis
Strapwort
Corydalis solida
Bird-in-a-bush
Corylus avellana
Hazel
Costus dubius
Spiral Flag
Costus elegans
Stepladder Ginger
Costus spiralis
Couroupita guianensis
Cannonball tree
Crambe maritima
Sea-kale
Crassocephalum crepidioides
Redflower Ragleaf
Crataegus laevigata
Midland Hawthorn
Crepis capillaris
Smooth Hawk's-beard
Crepis foetida
Stinking Hawk's-beard
Crepis vesicaria
Beaked Hawk's-beard
Crinum jagus
Saint Christopher's Lily
Crocosmia x crocosmiiflora
Montbretia
Crocus tommasinianus
Early Crocus
Crotalaria pallida
Crotalaria
Croton bonplandianus
Cruciata laevipes
Crosswort
Cyanthillium cinereum
Little Ironweed
Cymbidium ensifolium
Four-season Orchid
Cynoglossum officinale
Hound's-tongue
Cynosurus cristatus
Crested Dog's-tail
Cyperus brevifolia
Cyperus fuscus
Brown Galingale
Cyperus javanicus
Javanese Flatsedge
Cyperus mindorensis
White-Head Spike Sedge
Cypripedium calceolus
Lady's-slipper
Cytisus scoparius
Broom