| Threatened |
|---|
| Cacalia diversifolia | Variable-leaved Indian plantain |
| Calamintha ashei | Ashe's savory; lavender basil |
| Calamovilfa curtissii | Curtiss' reedgrass; Curtiss' sand grass |
| Calopogon barbatus | Bearded grass pink |
| Carex baltzelli | Baltzell's sedge |
| Cleistes divaricata | Rosebud orchid; spreading pogonia |
| Drosera intermedia | Water sundew |
| Endangered |
|---|
| Callirhoe papaver | Poppy mallow |
| Calopogon multiflorus | Many-flowered grass pink |
| Calycanthus floridus | Sweetshrub |
| Calyptranthes zuzygium | Myrtle of the river |
| Calystegia catesbaeiana | Catesby's bindweed |
| Campanula robinsiae | Robins' (=Chinsegut) bellflower |
| Campylocentrum pachyrrhizum | Leafless orchid |
| Campyloneurum angustifolium | Narrow strap fern |
| Campyloneurum costatum | Tailed strap fern |
| Campyloneurum phyllitidus | Long strap fern |
| Canella winteriana | Wild cinnamon |
| Cassia keyensis (=Chaemecrista lineata var. keyensis) | Big Pine partridge pea; Florida Keys senna; Key cassia |
| Catesbaea parviflora | Small-flowered (=dune) lily-thorn |
| Catopsis berteroniana | Powdery (=yellow) catopsis |
| Catopsis floribunda | Many-flowered air plant |
| Catopsis nutans | Nodding catopsis |
| Celtis iguanaea | Iguana hackberry |
| Celtis pallida | Spiny hackberry |
| Cereus eriophorus | Indian River prickly apple |
| Cereus gracilis | West coast prickly apple |
| Cereus pentagonus | Dildoe (=barbed wire) cactus |
| Cereus robinii | Tree cactus |
| Chamaesyce cumulicola | Sand dune spurge |
| Chamaesyce deltoidea ssp. deltoidea | Wedge (=deltoid; =rockland) spurge |
| Chamaesyce garberi | Garber's spurge |
| Chamaesyce porteriana | Porter's spurge |
| Cheilanthes microphylla | Southern lip fern |
| Chionanthus pygmaeus | Pygmy fringetree |
| Chrysophyllum oliviforme | Satinleaf |
| Chrysopsis cruiseana (=C. gossypinus crioseana) | Cruise's golden aster |
| Chrysopsis floridana | Florida golden aster |
| Cienfuegosia yucatanensis (=C. heterophylla) | Yellow hibiscus |
| Cladonia perforata | Perforate reindeer lichen; deer moss |
| Clitoria fragrans | Pigeon-wing (=sandhill) butterfly-pea |
| Clusia rosea | Balsam apple |
| Coccothrinax argentata | Silver palm |
| Colubrina cubensis | Colubrina |
| Conradina breviflora | Short-leaved rosemary |
| Conradina etonia | Etonia rosemary |
| Conradina glabra | Apalachicola (=panhandle) rosemary |
| Conradina grandiflora | Large-flowered rosemary |
| Corallorhiza odontorhiza | Autumn coralroot |
| Cardia sebestena | Geiger tree |
| Cornus alternifolia | Pagoda dogwood |
| Cranichis muscosa | Moss orchid |
| Crataegus phaenopyrum | Washington thorn |
| Croomia pauciflora | Few-flowered croomia |
| Crossopetalum ilicifolium | Christmas berry |
| Crossopetalum rhacoma | Rhacoma |
| Crotolaria avonensis | Avon Park rattlebox; Avon Park harebells |
| Cryptotaenia canadensis | Honewort |
| Ctenitis sloanei | Red-hair comb fern; Florida tree fern |
| Ctenitis submarginalis | Brown-hair comb fern |
| Cucurbita okeechobeensis | Okeechobee gourd; Indian pumpkin |
| Cupania glabra | Cupania |
| Cyrtopodium punctatum | Cowhorn (=cigar) orchid |
| Deeringothamnus pulchellus | White squirrel-banana; beautiful pawpaw |
| Deeringothamnus rugelii | Yellow squirrel-banana; Rugel's pawpaw |
| Delphinium carolinianum | Carolina larkspur |
| Dennstaedtia bipinnata | Cuplet (=hay-scented) fern |
| Dicerandra christmanii | Garrett's mint |
| Dicerandra cornutissima | Long-spurred balm; Robins' mint |
| Dicerandra frutescens | Scrub balm; Lloyd's mint |
| Dicerandra immaculata | Lakela's (=Olga's) mint |
| Digitaria pauciflora | Florida pineland crabgrass |
| Dodecatheon meadia | Shooting star |
| Drosera filifolia | Dew-thread |
Protected Plants: C-D