| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Cherokee' | Large | Dark-Green | Medial | Yellow | Sport | Pale-Lavender | July into August | Wade, Van | --NR-- |
| 'Cheyenne' | Large | Med-Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chickasaw' | Large | Blue/Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Cornstalk' | Giant | Med-Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Crazy Horse' | Giant | Blue/Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Killbuck' | Giant | Blue/Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Little Turtle' | Giant | Blue/Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Sitting Bull' | Giant | Blue/Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chief Thundercloud' | Giant | Blue/Green | - | - | Hybrid | - | - | Wade, Van | --NR-- |
| 'Chief White Cloud' | Giant | Blue/Green | - | - | Hybrid | Pale-Lavender | August | Wade, Van | .2007 |
| 'Chief Yellow Head' | Large | Light-Green | | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Chinese Gold' | Medium | Yellow | - | - | Hybrid | - | August to September | Wade, Van & Walek, Kevin | .2009 |
| 'Chippewa' (Wade) | Giant | Blue/Green | - | - | Hybrid | Pale-Lavender | July into August | Wade, Van | --NR-- |
| 'Choctaw' | Giant | Blue/Green | - | - | Hybrid | Near-White | June into July | Wade, Van | .2007 |
| 'Clear Fork Blue' | Giant | Blue/Green | - | - | Unknown | Pale-Lavender | June into July | Wade, Van | --NR-- |
| 'Clear Fork River Valley' | Large | Dark-Green | - | - | Hybrid | Near-White | June into July | Wade, Van | .2007 |
| 'Clearfork Blue' | Large | Blue/Green | | | Unknown | | | Wade, Van | --NR-- |
| 'Clearfork Delight' | Large | Dark-Green | Medial | Yellow | Sport | Pale-Lavender | July | Wade, Van | --NR-- |
| 'Clearfork Green' | Medium | Dark-Green | - | - | Unknown | Pale-Lavender | June into July | Wade, Van | .1999 |
| 'Comanche' | Large | Blue/Green | - | - | Sport | Near-White | June into July | Wade, Van | --NR-- |
| 'Constellation Andromeda' | Large | Blue/Green | Marginal | Yellow | Unknown | - | - | Wade, Van | --NR-- |
| 'Cosmos' | Small | Dark-Green | Medial | White | Unknown | | | Wade, Van | --NR-- |
| 'Cree' | Giant | Blue/Green | - | - | Hybrid | Near-White | June into July | Wade, Van | .2007 |
| 'Creek' | Medium | Blue/Green | - | - | Hybrid | Pure-White | June | Wade, Van | .2007 |
| 'Crow' | Medium | Dark-Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Cup of Gold' | Medium | Yellow | - | - | Unknown | - | - | Wade, Van | --NR-- |
| 'Cyrus' | Giant | Dark-Green | - | - | Unknown | - | - | Wade, Van | --NR-- |
|