Calicoplant 
California Barrel Cactus 
California Buckwheat 
Calligonum comosum 
Candleholder Cactus 
Cape leadwort 
Cape Sundew 
Carolina springbeauty 
Caroxylon canescens 
Caroxylon inerme 
Caroxylon orientale 
Caroxylon tetrandrum 
Carthusian Pink 
Centinodia leñosa 
Centipede Plant 
Cephalocereus senilis 
Cerastium alpinum 
Cerastium decalvans subsp. leontopodium 
Cerastium dichotomum 
Cerastium dubium 
Cerastium inflatum 
Cereus forbesil 
Chinese Rhubarb 
Christmas Cactus