Calamintha

Callirhoe

Campanula

Candle Larkspur

Candytuft

Cardinal Flower 

Carpathian Bellflower

Carpet Weed

Catchfly

Catmint 

Centaurea

Cheddar Pinks

Chelone

Chinese Globeflower 

Clematis

Clustered Bellflower

Columbine 

Coneflower

Conoclinium

Convallaria

Coral Bells 

Coreopsis

Cranesbill 

Creeping Phlox 

Creeping Speedwell

Crocosmia

Culver's Root