| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'A Dog of Flanders' | Medium | Med-Green | - | - | Hybrid | - | - | Philips, Hugo | .2010 |
| 'Aachen' | Medium | Blue/Green | - | - | Hybrid | - | June into July | Malloy, Alex | .2005 |
| 'Abana' | Medium | Dark-Green | Medial | Yellow | Sport | - | July into August | Dupre, Dirk | .2010 |
| 'Abbey Road' | Medium | Dark-Green | Marginal | White | Unknown | - | June into July | Wasitis, Chick | .2014 |
| 'Aberdeen Mountain' | | - | | - | Duplicate | - | - | Duplicate Name | |
| 'Abiqua Big Sky' | Giant | Blue/Green | - | - | Unknown | - | June into July | Purtymun, Charles & Ruh, Peter | .2008 |
| 'Abiqua Chelais' | Medium | Med-Green | - | - | Unknown | - | - | Purtymun, Charles | --NR-- |
| 'Ahr' | Medium | Blue/Green | - | - | Hybrid | - | - | Klose, Heinz | --NR-- |
| 'Ahwaneeh' | Large | Light-Green | - | - | Hybrid | Pure-White | July into August | Syre-Herz, Ursula | .1990 |
| 'Aichi' | Medium | Dark-Green | - | - | Sport | Light-Purple | August to September | Unknown | --NR-- |
| 'Aksarben' | Giant | Blue/Green | - | - | Hybrid | Near-White | June into July | Geissler, Julia & Ruh, Peter | .1988 |
| 'Alabama Bowl' | Large | Blue/Green | - | - | Hybrid | Near-White | July | Suggs, Natalee | .1986 |
| 'Alabama Gold' | Large | Yellow | - | - | Hybrid | Pale-Lavender | June into July | Suggs, Natalee | .1986 |
| 'Alabama Sunrise' | Large | Light-Green | - | - | Unknown | - | - | Solberg, Robert | .2011 |
| 'Alaska Gold' | Small | Yellow | - | - | Unknown | Light-Purple | - | Jentsch, Klaus | --NR-- |
| 'Alaskan Halo' | Large | Med-Green | Marginal | White | Sport | Pale-Lavender | July into August | Ruh, Peter | .1997 |
| 'Allegan Emperor' | Giant | Blue/Green | - | - | Hybrid | Pale-Lavender | July | Herrema, Ken, Deshane, H. & Ruh, Peter | .2000 |
| 'Allegan Fog' | Medium | Med-Green | Medial | Speckles | Hybrid | Pale-Lavender | July into August | Herrema, Ken & Ruh, Peter | .2000 |
| 'Allegan Gent' | Large | Blue/Green | Marginal | Speckles | Sport | Near-White | June into July | Herrema, Ken & Ruh, Peter | .2000 |
| 'Allegan Peppermint' | Medium | Light-Green | - | - | Unknown | - | - | Unknown | --NR-- |
| 'Allegan Peppermint Twist' | | - | | - | Unknown | - | - | Herrema, Ken | --NR-- |
| 'Allegan Webb' | Large | - | | - | Unknown | - | - | Herrema, Ken | --NR-- |
| 'Allegheny Moon' | Medium | Med-Green | - | - | Hybrid | - | - | Malloy, Alex | --NR-- |
| 'Allegheny River' | Medium | Med-Green | - | - | Hybrid | Pure-White | August | Malloy, Alex | .2005 |
| 'Alligator Alley' | Medium | Blue/Green | Medial | Yellow | TC Sport | Near-White | June into July | Walters Gardens | .2012 |
| 'Alma' | Small | Yellow | - | - | Unknown | Light-Purple | August | Krossa, Gus & Ruh, Peter | .1995 |
| 'Alpine Aire' | Medium | Yellow | - | - | Hybrid | Pale-Lavender | July into August | Minks, Eldren | .1980 |
| 'Alpine Dream' | Medium | Med-Green | - | - | Hybrid | Light-Purple | July | Savory, Robert | .1982 |
| 'Alpine Ice' | Large | Med-Green | Marginal | White | Sport | Near-White | July into August | Green Mountain Hosta | --NR-- |
| 'Amakazari' | Medium | Dark-Green | - | - | Unknown | - | - | Nakayama, Toyozo | --NR-- |
| 'An Arrow for Easton' | Miniature | Med-Green | Marginal | White | Unknown | - | - | Goodwin, Randy | .2014 |
| 'Angel from Montgomery' | Medium | Med-Green | Marginal | Yellow | Unknown | - | June into July | Wasitis, Chick | .2014 |
| 'Ansty' | Medium | Blue/Green | - | - | Unknown | - | - | Simon, Dr Hans | --NR-- |
| 'Antioch' | Large | Med-Green | Marginal | Creamy White | Unknown | Pale-Lavender | July into August | Tompkins, Cynthia & Hofer, Paul & Ruh, Peter | .1979 |
| 'Appalachian Beauty' | Large | Med-Green | Marginal | Yellow | TC Sport | Near-White | June into July | Zilis, Mark | .2003 |
| 'Appalachian Spring' | Medium | Light-Green | - | - | Hybrid | Near-White | June into July | Malloy, Alex | .2004 |
| 'Arc de Triomphe' | Large | Blue/Green | Marginal | Creamy White | Hybrid | Pale-Lavender | July into August | Elslager, Ed | .2000 |
| 'Arctic Blast' | Medium | Blue/Green | - | - | Hybrid | Light-Purple | July | Carlson, Monty & Julie | .2019 |
| 'Arctic Circle' | Medium | Med-Green | Marginal | White | Unknown | Pale-Lavender | July into August | Tompkins, Chet & Ruh, Peter & Jean | .2002 |
| 'Arctic Frost' | Large | Blue/Green | Streaked | Speckles | Sport | Pale-Lavender | August to October | Trucks, Gary | --NR-- |
| 'Arctic Rim' | Medium | Blue/Green | Marginal | White | Sport | Pale-Lavender | July into August | Lydell, Ransom | .1993 |
| 'Arctic Storm' | Large | Dark-Green | Streaked | Yellow | Unknown | - | - | Ternes, Nick | --NR-- |
| 'Arkansas Lad' | Giant | Med-Green | Marginal | White | Hybrid | Near-White | June into July | Metzger, C.D. | .2005 |
| 'Aspen Blue' | Medium | Blue/Green | - | - | Sport | Near-White | June into July | Hawes, James | --NR-- |
| 'Aspen Breeze' | Medium | Yellow | Marginal | White | TC Sport | Pale-Lavender | - | Scolnik, Patricia & Walek, Kevin | .2009 |
| 'Aspen Gold' | Large | Yellow | - | - | Hybrid | Near-White | June into July | Grapes, Vivian | .1986 |
| 'Aspen Green' | - | - | - | - | Duplicate | - | - | Duplicate Name | --NR-- |
| 'Aspen Pride' | Medium | Yellow | Marginal | Green | Unknown | - | - | Benedict, Dr Ralph (Herb) | --NR-- |
| 'Aspen White' | Medium | Yellow | Marginal | White | Sport | Near-White | June into July | Brill, Kirk | --NR-- |
| 'Atlantis' | Large | Blue/Green | Marginal | Yellow | Sport | Pale-Lavender | June into July | Hansen, Hans & Avent, Tony | .2004 |
| 'Audrey's Island' | Medium | Light-Green | Medial | Yellow | Sport | - | June into July | Moore, Betty | .2016 |
| 'Ayers Rock' | - | Med-Green | - | - | Unknown | - | - | Unknown | --NR-- |
| 'Azure Mediterranean' | Large | Med-Green | - | - | Unknown | Pale-Lavender | July into August | Helsley, Calvin | .1999 |
|