Catalpa (Indian bean) Catananche Catasetum (an orchid genus) Catha (khat tree) Catharanthus (Madagascar periwinkle) Catopsis Cattleya (an orchid genus) Caulophyllum Cautleya Cavendishia Ceanothus (California-lilac) Cedrela (toon) Cedronella Cedrus (cedar) Ceiba (kapok) Celastrus (staff-vine) Celmisia (New Zealand daisy, New Zealand aster) Celosia (cockscomb) Celtis (hackberry) Centaurea Centaurium Centradenia Centranthus (valerian) Cephalaria Cephalocereus Cephalophyllum Cephalotaxus (plum-yew) Ceraria Cerastium Ceratonia (St. John's bread, carob bean) Ceratopetalum (coachwood) Ceratophyllum Ceratopteris Ceratostigma Ceratozamia Cerbera (sea mango) Cercidiphyllum Cercis (Judas tree, redbud) Cercocarpus Cereus Ceropegia Cestrum Chadsia Chaenomeles (flowering quince) Chaenorhinum (dwarf snapdragon) Chaerophyllum Chamaecyparis (false cypress) Chamaecytisus Chamaedaphne Chamaedorea Chamaelirium Chamaemelum (chamomile) Chamaerops Chamelaucium (wax flower) Chasmanthe Chasmanthium Cheilanthes Cheiridopsis Chelidonium Chelone (turtlehead) Chiastophyllum Chiliotrichum Chilopsis (desert willow) Chimaphila Chimonanthus (wintersweet) Chimonobambusa Chionanthus (fringe tree) Chionochloa Chirita Chlidanthus Choisya Chonemorpha (Frangipani vine) Choricarpia (brush turpentine) Chorisia (floss silk tree) Chorizema Chrysalidocarpus Chrysanthemoides Chrysanthemum Chrysobalanus Chrysogonum Chrysolepis Chrysophyllum (star apple) Chrysothemis Chusquea Cibotium Cicerbita Cichorium (chicory, endive) Cimicifuga (bugbane) Cinnamomum (camphor laurel) Cionura Cirsium Cissus Cistus (rock rose, sun rose) Citharexylum (fiddlewood) Citrofortunella (hybrid) Citrus (lime, lemon) Cladanthus Cladrastis Clarkia Claytonia Cleistocactus Clematis Cleome (spider flower) Clerodendrum Clethra (summersweet) Cleyera Clianthus Clintonia Clitoria Clivia Clusia Clytostoma Cobaea Coccoloba (sea grape) Coccothrinax (thatch palm) Cocculus Cochlioda an orchid genus Cochlospermum (buttercup tree, Maximiliana) Cocos (coconut) Codiaeum (croton) Codonanthe Codonopsis Coelia Coelogyne (an orchid genus) Coffea (coffee tree) Coix Colchicum (autumn crocus, meadow saffron) Coleonema Colletia Collinsia Collomia Colocasia (taro) Colquhounia Columnea Colutea (bladder senna) Coluteocarpus Colvillea Combretum Comesperma Commelina (day flower, spiderwort, widow's tears) Commersonia Commidendrum Commiphora Comptonella Comptonia (Sweetfern) Conandron Congea Conicosia Coniogramme Conoclinium (mistflower) Conophytum Conospermum Conostylis Conradina Consolida (larkspur) Convallaria (lily-of-the-valley) Convolvulus (bindweed, morning glory) Copernicia (caranda palm, wax palm) Copiapoa syn. Pilocopiapoa Coprosma Coptis (goldthread) Cordia (bird lime tree) Cordyline Coreopsis (tickseed) Coriandrum (coriander cilantro) Coriaria Cornus (dogwood, cornel) Corokia Coronilla Correa Corryocactus Cortaderia (pampas grass, tussock grass) Cortusa Corybas (helmet orchid) Corydalis Corylopsis (winter-hazel) Corylus (hazel, filbert) Corymbia Corynocarpus Corypha Coryphantha Cosmos Costus Cotinus (smoke bush) Cotoneaster Cotula (brass buttons) Cotyledon Couroupita (cannonball tree) Crambe Craspedia Crassula + Crataegomespilus (graft chimera) Crataegus (hawthorn) × Crataemespilus (hybrid) Crepis Crescentia (calabash) Crinodendron Crinum Crocosmia (falling stars, montbretia) Crocus Crossandra (firecracker flower) Crotalaria (rattlepod) Croton Crowea Cryptanthus (earth stars) Cryptbergia (hybrid) Cryptocarya Cryptocoryne (water trumpet) Cryptomeria (sugi, Japanese cedar) Cryptostegia (Indian rubber vine) Cryptotaenia Ctenanthe Cucumis Cucurbita Cuminum Cunila Cunninghamia (China-fir) Cunonia Cupaniopsis (tuckeroo) Cuphea Cupressus (cypress) Cuprocyparis (hybrid) Curcuma Cussonia Cyananthus (trailing bellflower) Cyanotis