| Cabbage Palm |
Cordyline |
 |
| Calabash |
Crescentia alata |
 |
| Calamint |
Calamintha grandiflora |
|
| California Arrowhead |
Sagittaria montevidensis |
 |
| California Lilac (many) |
Ceanothus |
|
| California Lilac |
Ceanothus thyrsiflorus |
|
| Californian Allspice |
Calycanthus occidentalis |
|
| Californian Fuchsia |
Zauschneria californica |
|
| Californian Poppy |
Eschscholzia |
|
| Californian Poppy |
Eschscholzia californica |
 |
| Callianthemum |
Callianthemum |
|
| Camass (many) |
Camassia |
|
| Camass |
Camassia |
|
| Cambass |
Terminalia australis |
|
| Camel Thorn |
Acacia erioloba |
|
| Campion (many) |
Lychnis, Silene |
|
| Campion |
Lychnis viscaria |
|
| Campion |
Silene keiskei |
 |
| Canadian Burnet |
Sanguisorba canadensis |
|
| Canary Bird Vine, Canary Creeper |
Tropaeolum peregrinum |
|
| Canary Date Palm |
Phoenix canariensis |
|
| Canary Island Foxglove |
Isoplexis isabellina |
|
| Candytuft (many) |
Iberis |
|
| Candytuft |
Iberis pruitii candolleana gp |
|
| Candytuft |
Iberis umbellata |
|
| Canna |
Canna speciosa |
|
| Cannonball Tree |
Couropita |
|
| Cantabrian Morning Glory |
Convolvulus Morning Glory |
|
| Canterbury Bells |
Campanula medium v calycanthema |
|
| Cape Cowslip |
Lachenalia |
|
| Cape Daisy |
Osteospermum |
|
| Cape Daisy |
Dimorphotheca |
|
| Cape Figwort, Cape Fuchsia |
Phygelius aequalis |
|
| Cape Gooseberry |
Physalis peruviana |
 |
| Cape Honeysuckle |
Tecomaria capensis |
|
| Cape Mallow |
Anisodontea hypomandarum |
|
| Cape Marguerite |
Dimorphotheca |
|
| Cape Primrose |
Streptocarpus |
|
| Cape Tulip |
Homeria collina |
|
| Caper |
Capparis inermis |
|
| Cardoon |
Cynara cardunculus |
|
| Carob, Locust Bean |
Ceratonia siliqua |
|
| Carolina Allspice |
Calycanthus floridus |
|
| Carolina Jessamine |
Gelsemium sempervirens |
|
| Carpet Geranium |
Geranium incanum |
|
| Carpet Plant |
Alsobia (Episcia) dianthiflora |
|
| Cascade Penstemon |
Penstemon serrulatus |
|
| Cassia |
Cassia |
|
| Cassiope |
Cassiope hypnoides |
|
| Castor Bean, Castor Oil Plant |
Ricinus communis |
|
| Catchfly (many) |
Lychnis |
|
| Catchfly |
Lychnis viscaria |
|
| Catchfly (many) |
Silene |
|
| Catchfly |
Silene asterias |
|
