| Cultivar Name | Plant Size | Origin | Flower Color | Season | Source | Registered |
| 'Radiant Light' | Medium | Unknown | - | - | Livingston, Ron | --NR-- |
| 'Raspberry Beauty' | Medium | Hybrid | Light-Purple | August to September | Dishon, Jim | .1999 |
| 'Red Dragon' | Medium | Hybrid | Light-Purple | August | Livingston, Ron | --NR-- |
| 'Red Sails in the Sunset' | Small | Hybrid | Light-Purple | August | Van Ostrand, John | .2004 |
| 'Redgo' | Large | Unknown | - | - | Wade, Van | --NR-- |
| 'Regal Tot' | Small | Hybrid | Light-Purple | July into August | Zilis, Mark | .2010 |
| 'Renegade of Funk' | Large | Unknown | - | - | White, Jeff | --NR-- |
| 'Rich Uncle' | Large | Sport | Near-White | June | Malloy, Alex | .2002 |
| 'Rip Off' | Medium | Unknown | Pale-Lavender | - | Benedict, Dr Ralph (Herb) | --NR-- |
| 'Robust Giant' | Large | Unknown | - | June into July | Ruh, Peter & Ruh, Jean | .2005 |
| 'Ron Livingston' | Medium | Unknown | Light-Purple | August | Asch, Stuart | --NR-- |
| 'Rosedale Genevieve' | Large | Hybrid | Pale-Lavender | July | Hadrava, Jerry | .1999 |
| 'Rosedale Golden City' | Large | Unknown | Near-White | June into July | Hadrava, Jerry | .1999 |
| 'Roue de Fortune' | Small | Unknown | - | - | Bastille, Jocelyne | --NR-- |
| 'Roxsanne' | Large | Sport | Med-Lavender | July | Heemskerk, Gerardus | .2005 |
| 'Royal Scepter' | Small | Sport | Med-Lavender | July | Unknown | --NR-- |
| 'Rubber Ducky' | Medium | Unknown | Pale-Lavender | July into August | Schwarz, Jim | .1996 |
| 'Ruffled Pale Face' | Small | Unknown | - | July into August | Schulz, Ed | .2002 |
| 'Rusty's Tornado' | Medium | Unknown | - | - | Rouillier, Denis | --NR-- |
| 'Rutherford Birchard Hayes' | Medium | Unknown | Med-Lavender | - | Ruh, Peter & Ruh, Jean | .2010 |
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