Centaurium portense
Perennial Centaury
Centaurium pulchellum
Lesser Centaury
Centaurium scilloides
Perennial Centaury
Centranthus ruber
Red Valerian
Centratherum punctatum
Brazilian bachelor's button
Centrosema pubescens
Butterfly Pea
Cephalanthera damasonium
White Helleborine
Cephalanthera longifolia
Narrow-leaved Helleborine
Cephalanthera rubra
Red Helleborine
Cerastium alpinum
Alpine Mouse-ear
Cerastium arvense
Field Mouse-ear
Cerastium diffusum
Sea Mouse-ear
Cerastium fontanum
Common Mouse-ear
Cerastium glomeratum
Sticky Mouse-ear
Cerastium pumilum
Dwarf Mouse-ear
Cerastium semidecandrum
Little Mouse-ear
Cerastium tomentosum
Snow-in-summer
Cerastium x maureri
Ceratocapnos claviculata
Climbing Corydalis
Cercis siliquastrum
Judas-tree
Chaenomeles japonica
Japanese Quince
Chaenorhinum minus
Small Toadflax
Chaenorhinum origanifolium
Malling Toadflax
Chaerophyllum temulum
Rough Chervil
Chamaecereus silvestri
Peanut Cactus
Chamaecyparis lawsoniana
Lawson's Cypress
Chamaenerion angustifolium
Rosebay Willowherb
Chamelaucium uncinatum
Geraldton waxflower
Chelidonium majus
Greater Celandine
Chenopodiastrum murale
Nettle-leaved Goosefoot
Chenopodium vulvaria
Stinking Goosefoot
Chlorophytum comosum
Spider-plant
Christia vespertilionis
Red Butterfly Wing
Chromolaena odorata
Devil Weed
Chrysosplenium alternifolium
Alternate-leaved Golden-saxifrage
Chrysosplenium oppositifolium
Opposite-leaved Golden-saxifrage
Chrysothemis pulchella
Sunset Bells
Cichorium intybus
Chicory
Circaea alpina
Alpine Enchanter's-nightshade
Circaea lutetiana
Enchanter's-nightshade
Circaea x intermedia
Upland Enchanter's-nightshade
Cirsium acaule
Dwarf Thistle
Cirsium arvense
Creeping Thistle
Cirsium dissectum
Meadow Thistle
Cirsium eriophorum
Woolly Thistle
Cirsium heterophyllum
Melancholy Thistle
Cirsium oleraceum
Cabbage Thistle
Cirsium palustre
Marsh Thistle
Cirsium vulgare
Spear Thistle
Cirsium x celakovskianum
Cistus
Rockrose
Cistus salviifolius
Sage-leaved Rock-rose
Cladium mariscus
Great Fen-sedge
Claytonia perfoliata
Springbeauty
Claytonia sibirica
Pink Purslane
Clematis cirrhosa
Early Virgin's-bower
Clematis montana
Himalayan Clematis
Clematis rehderiana
Clematis serratifolia
Korean Clematis
Clematis vitalba
Traveller's-joy
Clematis x durandii
Clematis (x#durandii)
Cleome rutidosperma
Fringed Spider Flower
Cleome spinosa
Spiny Spiderflower
Cleome viscosa
Asian Spiderflower
Clerodendron paniculatum
Pagoda Flower
Clerodendron quadriloculare
Starburst Bush
Clinopodium acinos
Basil Thyme
Clinopodium ascendens
Common Calamint
Clinopodium vulgare
Wild Basil
Clitoria ternatea
Asian Pigeonwings