| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Caesar Salad' | Medium | Med-Green | - | - | Hybrid | Pale-Lavender | July into August | Avent, Tony | .2007 |
| 'Candy Box' | Small | Med-Green | Medial | White | Sport | Pale-Lavender | July into August | Van Eechaute, Danny | .2011 |
| 'Candy Cane' | Small | Blue/Green | Marginal | Yellow | Unknown | Deep-Purple | July | Banyai, Pauline & Elslager, Ed | .1995 |
| 'Candy Dish' (Hawes) | Large | Dark-Green | - | - | Hybrid | Pale-Lavender | August to October | Hawes, James | --NR-- |
| 'Candy Hearts' | Medium | Blue/Green | - | - | Hybrid | Pale-Lavender | July | Fisher, Eunice V. & Ruh, Peter | .1998 |
| 'Catch of the Day' | Large | Dark-Green | Medial | Yellow | Sport | Near-White | July into August | Solberg, Robert | .2013 |
| 'Cerveza' | Large | Light-Green | - | - | TC Sport | Med-Lavender | August | Zilis, Mark | .2009 |
| 'Chado' | Medium | Med-Green | Marginal | White | Hybrid | Pale-Lavender | July | Johnson, Greg | .2004 |
| 'Champagne' | Small | Blue/Green | Marginal | Yellow | Hybrid | Light-Purple | - | Savory, Robert | .1994 |
| 'Champagne and Caviar' | Small | Med-Green | Streaked | White | Sport | Light-Purple | July | Helsley, Calvin | .1999 |
| 'Champagne for All' | Medium | Dark-Green | Medial | White | Sport | Pale-Lavender | July into August | Van Eechaute, Danny | .2015 |
| 'Champagne Taste' | Medium | Light-Green | Marginal | White | Hybrid | Near-White | June | Schroeder, Bob & Schroeder, Barb & Petryszyn, Olga | .2012 |
| 'Cheese Ball' | Miniature | Light-Green | - | - | Unknown | Pale-Lavender | July into August | Goodwin, Randy | .2017 |
| 'Cheese Louise' | Large | Light-Green | - | - | Unknown | - | - | Hackbarth, Robert | .2015 |
| 'Cheesecake' | Miniature | Med-Green | Marginal | White | Sport | Light-Purple | August | Aden, Paul & Zilis, Mark | .2010 |
| 'Cheesehead' | Large | Light-Green | - | - | Unknown | - | - | Zilis, Mark | --NR-- |
| 'Cherries Jubilee' | Medium | Med-Green | Streaked | Speckles | Sport | Light-Purple | July into August | Malloy, Alex | .2001 |
| 'Cherry Berry' | Medium | Blue/Green | Marginal | White | Hybrid | Light-Purple | July into August | Lachman, Wm & Lachman, Eleanor | .1991 |
| 'Cherry Berry Streaked' | Medium | Blue/Green | Streaked | Speckles | Sport | Light-Purple | July into August | Schmid, Tom | --NR-- |
| 'Cherry Flip' | Medium | Dark-Green | - | - | Hybrid | Light-Purple | August | Zilis, Mark & Solberg, Robert | .2012 |
| 'Cherry Garcia' | - | - | - | - | Unknown | - | - | Herold, Roy | --NR-- |
| 'Cherry Pie' | Medium | Med-Green | Medial | White | Sport | Light-Purple | August to October | Machen, John | --NR-- |
| 'Cherry Tart' | Small | Yellow | - | - | Unknown | Light-Purple | August | Scheer, Alttara | --NR-- |
| 'Cherry Tomato' | Miniature | Med-Green | Medial | White | Sport | Deep-Purple | July | Walters Gardens | .2008 |
| 'Chili Fries' | Small | Dark-Green | Marginal | Yellow | Sport | Med-Lavender | August | Solberg, Robert | .2020 |
| 'Chocolate Mint' | Small | Dark-Green | - | - | Sport | Light-Purple | August to October | Schwarz, Karen & Zilis, Mark | .2014 |
| 'Chocolate Ripple' | Large | Dark-Green | Streaked | Yellow | Hybrid | Near-White | July into August | Kuenster, Rod | .2008 |
| 'Chocolate Soldier' | Small | Med-Green | Marginal | Yellow | Unknown | - | - | Hawes, James | --NR-- |
| 'Chopsticks' | Medium | Med-Green | - | - | Hybrid | Light-Purple | September to October | Herold, Roy & Walek, Kevin & The American Hosta Society | .2009 |
| 'Christmas Tart' | - | - | - | - | Unknown | Pale-Lavender | - | Unknown | --NR-- |
| 'Cinnabon' | Medium | Light-Green | | | Hybrid | Light-Purple | August to September | Bowe, Dave | .2021 |
| 'Cinnamon and Sugar' | Medium | Med-Green | - | - | Unknown | - | - | Herold, Roy | --NR-- |
| 'Cinnamon Bun' | Miniature | Med-Green | - | - | Unknown | - | - | Herold, Roy | --NR-- |
| 'Cinnamon Sticks' | Medium | Med-Green | - | - | Hybrid | Light-Purple | August to October | Herold, Roy & Walek, Kevin & The American Hosta Society | .2009 |
| 'Cinnamon Twist' | Medium | Med-Green | - | - | Unknown | - | - | Herold, Roy | --NR-- |
| 'Clambake' | Large | Blue/Green | - | - | Hybrid | Pale-Lavender | July into August | Goodwin, Randy | .2000 |
| 'Clementine' | Small | Med-Green | - | - | Hybrid | Pale-Lavender | July | Husemann, Jim & Schulz, Ed | .2007 |
| 'Cloud Lime' | Medium | Light-Green | - | - | Unknown | - | - | Serafin, Viktoria | --NR-- |
| 'Coconut Custard' | Miniature | Yellow | - | - | Hybrid | Med-Lavender | July into August | Solberg, Robert | .2007 |
| 'Coffee Break' | Small | Blue/Green | Streaked | White | Sport | Pale-Lavender | June into July | Wong, Tony | --NR-- |
| 'Colored Lollipop' | Small | Dark-Green | Streaked | White | Unknown | - | - | Van den Top, Jan | --NR-- |
| 'Colored Muffin' | Medium | Blue/Green | Streaked | Yellow | Nat-Sport | Deep-Purple | July | Van den Top, Jan | --NR-- |
| 'Cookie Crumbs' | Miniature | Med-Green | Marginal | White | TC Sport | Light-Purple | July | Zilis, Mark | .2002 |
| 'Cookie Monster' | Large | Yellow | - | - | Hybrid | - | - | Kuk, Bob | --NR-- |
| 'Cool As A Cucumber' | Large | Med-Green | Medial | White | Sport | Pale-Lavender | June into July | Walters Gardens | .2012 |
| 'Corkscrew' | Small | Med-Green | - | - | Hybrid | Light-Purple | August to October | Solberg, Robert | .2003 |
| 'Corn Muffins' | Large | Yellow | - | - | Hybrid | Light-Purple | July into August | Beilstein, Doug & Zilis, Mark | .2009 |
| 'Cornbread' | | | | | Hybrid | | | Balitewicz, Bob | --NR-- |
| 'Cosmic Beer Brat' | Medium | Blue/Green | | | Hybrid | Pale-Lavender | July into August | Kuenster,Rod | .2021 |
| 'Cosmic Eye Candy' | Medium | Med-Green | Streaked | Yellow | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2014 |
| 'Cosmic Moonshine' | Large | Blue/Green | Streaked | Yellow | Hybrid | Med-Lavender | June into July | Kuenster, Rod | .2012 |
| 'Cosmic Spotted Cow' | Medium | Med-Green | Streaked | White | Hybrid | Near-White | June into July | Kuenster, Rod | .2011 |
| 'Cotton Candy' | Medium | Med-Green | Streaked | Speckles | Sport | Med-Lavender | July into August | Zilis, Mark | .2009 |
| 'Cracker Crumbs' | Miniature | Yellow | Marginal | Green | Sport | Light-Purple | July | Solberg, Robert | .2002 |
| 'Cracker Jack' | Small | Med-Green | Marginal | Yellow | TC Sport | Light-Purple | July into August | Zilis, Mark | .2011 |
| 'Crainberry Wine' | Large | Yellow | Marginal | Yellow | Unknown | - | - | de Rooij, Piet | --NR-- |
| 'Cranberries and Cream' | Small | Dark-Green | Streaked | White | Unknown | - | - | Silvers, Bill | --NR-- |
| 'Cranberry Relish' | - | - | - | - | Duplicate | - | - | Duplicate Name | --NR-- |
| 'Cranberry Wine' | Small | Light-Green | - | - | Hybrid | - | - | Sisson, Kathie | --NR-- |
| 'Cream Cheese' | Small | Med-Green | Marginal | Creamy White | Hybrid | Light-Purple | August to October | Lachman, Wm & Lachman, Eleanor | .1991 |
| 'Cream Delight' | Medium | Med-Green | Medial | White | Sport | Light-Purple | July | Ford, Richard & Ford, Mary | --NR-- |
| 'Cream Edge Seer' | - | - | - | - | Unknown | - | - | Tompkins, Chet | --NR-- |
| 'Cream Puff' | - | - | - | - | Unknown | - | - | Klose, Heinz | --NR-- |
| 'Cream Topping' | Medium | Blue/Green | Medial | White | Sport | Med-Lavender | - | Heemskerk, Gerardus | --NR-- |
| 'Creamsicle' | Medium | Light-Green | - | - | Unknown | - | - | Purvis, Owen & Purvis, Sue | --NR-- |
| 'Crème Brûlée' | Medium | Med-Green | Marginal | Yellow | Sport | Med-Lavender | July into August | Johnson, Greg | .2004 |
| 'Creme Caramel' | - | - | - | - | Unknown | - | - | Meyer, Bill & Brashear, Carol | --NR-- |
| 'Creme de Menthe' | Large | Blue/Green | Marginal | White | TC Sport | Near-White | June into July | Zilis, Mark | --NR-- |
| 'Creme Latte' | Small | Dark-Green | Medial | White | Sport | Pale-Lavender | July | Barta, Jack & Ziarek, Ken | --NR-- |
| 'Crepe Suzette' | Miniature | Med-Green | Marginal | White | Hybrid | Pale-Lavender | July into August | Lachman, Wm & Lachman, Eleanor | .1986 |
| 'Crispy Critters' | Small | Yellow | - | - | Unknown | - | - | Avent, Tony | --NR-- |
| 'Croutons' | Miniature | Med-Green | Streaked | White | TC Sport | Light-Purple | June into July | Zilis, Mark | .2003 |
| 'Crowned Imperial' | Medium | Blue/Green | Marginal | White | Sport | Pale-Lavender | July into August | Walters Gardens | .1988 |
| 'Crows Landing Lime Sorbet' | Large | Light-Green | Marginal | White | Unknown | - | August to September | Stygall, Patsy | .2011 |
| 'Crows Landing Rippled Truffles' | Medium | Med-Green | Marginal | Yellow | Unknown | - | August to September | Stygall, Patsy | .2011 |
| 'Crumb Cake' | Small | Dark-Green | - | - | Hybrid | Light-Purple | July | Solberg, Robert | .2008 |
| 'Cup of Cheer' | - | - | - | - | Unknown | - | - | Housworth, Jere | --NR-- |
| 'Cup of Cream' | Small | Yellow | - | - | Unknown | - | - | Woods, Doyle | --NR-- |
| 'Curly Fries' | Medium | Light-Green | - | - | Hybrid | Deep-Purple | August | Solberg, Robert | .2008 |
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