| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Calypso' | Small | Blue/Green | Marginal | White | Hybrid | Light-Purple | July into August | Lachman, Wm & Eleanor | .1987 |
| 'Candy Box' | Small | Med-Green | Medial | White | Nat-Sport | Pale-Lavender | July into August | Van Eechaute, Danny | .2011 |
| 'Capricorn' | Large | Blue/Green | - | - | Hybrid | - | June into July | Husemann, Jim | .2009 |
| 'Cemetery Road' | Large | Med-Green | Streaked | White | Hybrid | Light-Purple | August to September | Kuenster, Rod | .2011 |
| 'Checkerboard II' | Large | Med-Green | - | - | Unknown | Pale-Lavender | July | Unknown & Walek, Kevin | .2009 .2018 |
| 'Chocolate Ripple' | Large | Dark-Green | Streaked | Yellow | Hybrid | Near-White | July into August | Kuenster, Rod | .2008 |
| 'Chuck's Sweetheart' | Small | Med-Green | - | - | Unknown | Med-Lavender | - | Purtymun, Charles | .2009 |
| 'Coach Jim Brainerd' | Small | Light-Green | Streaked | White | Unknown | - | July into August | Freeman, Franc & Sally | .2011 |
| 'Coach Paul Castro' | Medium | Med-Green | Streaked | Yellow | Hybrid | - | August to September | Freeman, Franc | .2010 |
| 'Cobra's Lair' | Medium | Blue/Green | - | - | Hybrid | - | - | Philips, Hugo | .2010 |
| 'Colesburg Wiggles' | Medium | Med-Green | Marginal | Yellow | Unknown | Light-Purple | July into August | Hackbarth, Robert | .2015 |
| 'Color Riot' | Small | Med-Green | Medial | White | Hybrid | - | - | Tompkins, Chet & Cynthia & Ruh, Peter | --NR-- |
| 'Cornerstone' | Giant | Blue/Green | - | - | Hybrid | Near-White | July | Hanna, Clarence | .2013 |
| 'Cosmic Brew' | Large | Blue/Green | Streaked | Yellow | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2010 |
| 'Cosmic DNA' | Giant | Blue/Green | Streaked | Yellow | Hybrid | Near-White | June into July | Kuenster, Rod | .2012 |
| 'Cosmic Eye Candy' | Medium | Med-Green | Streaked | Yellow | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2014 |
| 'Cosmic Flash' | Large | Dark-Green | Streaked | White | TC Sport | - | July into August | Kuenster, Rod | .2010 |
| 'Cosmic Hot Mama' | Large | Med-Green | Streaked | White | Hybrid | Near-White | June into July | Kuenster, Rod | .2011 |
| 'Cosmic Journey' | Medium | Dark-Green | Streaked | Speckles | Hybrid | Med-Lavender | June into July | Kuenster, Rod | .2010 |
| 'Cosmic Joy' | Large | Dark-Green | Marginal | Yellow | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2012 |
| 'Cosmic Moon' | Large | Blue/Green | - | - | Hybrid | Near-White | July into August | Kuenster, Rod | .2015 |
| 'Cosmic Patchwork' | Medium | Med-Green | Streaked | Yellow | Hybrid | Near-White | June into July | Kuenster, Rod | .2014 |
| 'Cosmic Warrior' | Medium | Med-Green | Streaked | Yellow | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2014 |
| 'Cowabunga' | Large | Light-Green | Marginal | White | Unknown | - | - | Asch, Stuart | .2010 |
| 'Cute as a Button' | Miniature | Med-Green | Medial | White | Unknown | Pale-Lavender | - | Goodwin, Randy | .2009 |
| 'Cutting Edge' | Large | Blue/Green | - | - | Hybrid | Pale-Lavender | July into August | Benedict, Dr R. (Herb) & Gowen, Hideko | .1999 |
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