Celtis occidentalis 'Chicagoland'

Celtis occidentalis 'Prairie Pride'

Celtis tenuifolia

Centaurea barbeyi

Centaurea cheiranthifolia

Centaurea dealbata

Centaurea fischeri

Centaurea hypoleuca 'John Coutts'

Centaurea macrocephala

Centaurea montana

Centaurea montana 'Amethyst Dream'

Centaurea montana 'Amethyst In Snow'

Centranthus longiflorus

Centranthus ruber 'Coccineus'

Centranthus ruber 'Pretty Betsy'

Centranthus ruber 'Rosenrot'

Centratherum intermedium 'Pineapple Sangria'

Cephalanthera rubra

Cephalanthus occidentalis

Cephalanthus occidentalis 'SMCOSS'

Cephalanthus occidentalis 'Sputnik'

Cephalaria leucantha

Cephalocereus palmeri

Cephalocereus polylophus

Cephalocereus senilis