| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Rachel' | Large | Dark-Green | Marginal | Yellow | Hybrid | Deep-Purple | July into August | Kuk, Bob | .2005 |
| 'Rainbow Glenn' | Medium | Light-Green | Streaked | White | Hybrid | Pale-Lavender | July | Kuenster, Rod | .2005 |
| 'Ralph' | Large | Blue/Green | Medial | White | Unknown | Near-White | July | O'Harra, Russ | --NR-- |
| 'Ralph's Legacy' | Small | Med-Green | Streaked | Speckles | Unknown | - | July into August | Zolock, Steve & Zolock, Sarah | .2000 |
| 'Raul Bunyan' | - | - | - | - | Duplicate | - | - | Duplicate Name | --NR-- |
| 'Ravinia' | Small | Med-Green | Marginal | White | Sport | Med-Lavender | August | Goodwin, Randy | .2013 |
| 'Ray of Hope' | Miniature | Med-Green | Streaked | Yellow | Sport | Light-Purple | August | Tower, Alan & Solberg, Robert | .2005 |
| 'Razz'n Rick' | Large | Med-Green | Streaked | Yellow | Unknown | - | August to September | Schmidt, Bevie | .2009 |
| 'Ready Eddy' | Small | Blue/Green | - | - | Unknown | - | - | Benedict, Dr Ralph (Herb) | --NR-- |
| 'Ready Freddy' | Giant | Dark-Green | - | - | Unknown | Near-White | June into July | Asch, Stuart | .2010 |
| 'Rebecca' | Large | Yellow | - | - | Hybrid | Pale-Lavender | July | Zilis, Mark | .2004 |
| 'Reddy Eddy' | Large | Dark-Green | - | - | Unknown | - | August to September | Benedict, Dr Ralph (Herb) & Kuenster, Rod | .2010 |
| 'Reggie Rising' | Medium | Light-Green | Streaked | White | Unknown | - | - | Unknown | --NR-- |
| 'Richmond' | Medium | Med-Green | Marginal | Yellow | Hybrid | Pale-Lavender | July | Seaver, Mildred | .2004 |
| 'Rick's Blessings' | - | - | - | - | Unknown | - | - | Unknown | --NR-- |
| 'Rifle Ron' | Medium | Dark-Green | - | - | Unknown | - | - | Schmidt, Bevie | --NR-- |
| 'Risa' | Small | Med-Green | - | - | Unknown | Med-Lavender | July into August | Dupre, Dirk | .2006 |
| 'Robb's Dream' | Large | Med-Green | Streaked | White | Unknown | - | June into July | McWilliams, Robb & Philips, Hugo | .2011 |
| 'Robert's Rapier' | Medium | Dark-Green | Medial | White | Sport | Pale-Lavender | July into August | Keller, Robert | .1996 |
| 'Robin's Pride' | Large | Blue/Green | - | - | Unknown | - | June into July | Goodwin, Randy | .2000 |
| 'Rob's Rag' | | - | | - | Unknown | - | - | Unknown | --NR-- |
| 'Roderick' | Giant | Blue/Green | - | - | Unknown | Pale-Lavender | - | O'Harra, Russ | .1999 |
| 'Rod's Gold' | Medium | Yellow | - | - | Hybrid | Pale-Lavender | June into July | Kuenster, Rod | .2004 |
| 'Romy's Rescue' | - | - | - | - | Hybrid | - | - | Sneyers, Rob | --NR-- |
| 'Rosaleen' | Small | Dark-Green | Marginal | White | Hybrid | Light-Purple | June into July | Gilligan, Madelon | .2017 |
| 'Rosanne' | Small | Med-Green | - | - | Unknown | - | - | O'Harra, Russ | .1999 |
| 'Rose Ann' | - | - | - | - | Unknown | - | - | Tompkins, Chet | --NR-- |
| 'Rosedale Barnie' | Medium | Dark-Green | - | - | Hybrid | Light-Purple | July | Hadrava, Jerry | .1999 |
| 'Rosedale Genevieve' | Large | Light-Green | - | - | Hybrid | Pale-Lavender | July | Hadrava, Jerry | .1999 |
| 'Rosedale Grampa Jack' | Small | Light-Green | Medial | Yellow | Unknown | Light-Purple | July | Hadrava, Jerry | --NR-- |
| 'Rosedale Jack of Hearts' | Medium | Dark-Green | Streaked | Yellow | Hybrid | Med-Lavender | July | Hadrava, Jerry | .2000 |
| 'Rosedale Jack of Spades' | Medium | Med-Green | Streaked | Yellow | Hybrid | Med-Lavender | July into August | Hadrava, Jerry | .2000 |
| 'Rosedale Justin's Folly' | Small | Yellow | Marginal | Green | Unknown | Light-Purple | July | Hadrava, Jerry | --NR-- |
| 'Rosedale Lela Mae' | Large | Blue/Green | Marginal | Yellow | Unknown | Near-White | June | Hadrava, Jerry | .1999 |
| 'Rosemary' | Large | Med-Green | Marginal | Yellow | Hybrid | Near-White | July into August | Parks, David | .2019 |
| 'Rosie Posie' | Large | Dark-Green | Marginal | White | Hybrid | Med-Lavender | August to September | Krul, Nancy & Belle Gardens | .1994 |
| 'Rosy' | Medium | Blue/Green | - | - | Unknown | - | - | Klose, Heinz | --NR-- |
| 'Roxsanne' | Large | Light-Green | - | - | Sport | Med-Lavender | July | Heemskerk, Gerardus | .2005 |
| 'Roxy Moxy' | Small | Med-Green | Marginal | White | Sport | Pale-Lavender | July | Meyer, Roxanne | .2006 |
| 'Royal Highness Abrielle' | - | - | - | - | Unknown | - | - | Unknown | --NR-- |
| 'Royal Susan' | Large | Med-Green | Streaked | White | Sport | Pale-Lavender | August | Benedict, Dr Ralph (Herb) | --NR-- |
| 'Roy's Pink' | Small | Med-Green | - | - | Hybrid | Light-Purple | August | Benedict, Dr Ralph (Herb) & Walek, Kevin | .2009 |
| 'Ruben' | Small | Yellow | - | - | Unknown | - | - | Silvers, Bill | --NR-- |
| 'Ruby' | Small | Med-Green | - | - | Hybrid | Light-Purple | August to September | Savory, Dennis | .2013 |
| 'Ruby Desires' | Medium | Dark-Green | Marginal | Yellow | Unknown | - | - | Klotz, Ruby | --NR-- |
| 'Ruby Slippers' | Medium | Med-Green | - | - | Hybrid | Light-Purple | September | Ward, Dr Dick & Ward, Jane | .1999 |
| 'Ruby Tuesday' | Small | Med-Green | - | - | Unknown | - | - | Herold, Roy | --NR-- |
| 'Rudolph' | - | - | - | - | Duplicate | - | - | Duplicate Name | --NR-- |
| 'Rudolph Golden' | - | - | - | - | Duplicate | - | - | Duplicate Name | --NR-- |
| 'Rudolph's #1' | Large | Dark-Green | - | - | Unknown | - | - | Rudolph, Thelma | --NR-- |
| 'Rufus Rider' | Medium | Dark-Green | Marginal | White | Hybrid | Pale-Lavender | July into August | Livingston, Ron | --NR-- |
| 'Runaround Sue' | Medium | Med-Green | Marginal | Yellow | Hybrid | Light-Purple | - | Wasitis, Chick | --NR-- |
| 'Russell Square' | Medium | Blue/Green | - | - | Unknown | - | - | Crockett, Clyde | --NR-- |
| 'Rusty Bee' | Medium | Med-Green | - | - | Hybrid | Light-Purple | July | Malloy, Alex | .1998 |
| 'Rusty's Fine Line' | Large | Dark-Green | Medial | White | Sport | Pale-Lavender | July into August | Rouillier, Denis | --NR-- |
| 'Ruth' | Medium | Blue/Green | - | - | Sport | Pale-Lavender | June into July | Schwarz, Jim & Schwarz, Karen | .2014 |
| 'Ruth's Green Edger' | Medium | Med-Green | - | - | Unknown | - | - | Unknown | --NR-- |
| 'Ryan's Big One' | Giant | Blue/Green | - | - | Hybrid | Near-White | June into July | Englerth, Lawrence & Ryan (Unknown) | .1982 |
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