| Cultivar Name | Plant Size | Origin | Flower Color | Season | Source | Registered |
| 'H. D. Thoreau' | Giant | Hybrid | Pale-Lavender | July into August | Purtymun, Charles | .1999 |
| 'Hadspen Blue' | Large | Unknown | Pale-Lavender | July into August | Smith, Eric & Aden, Paul | .1976 |
| 'Hadspen Dolphin' | Giant | Unknown | - | - | Unknown | --NR-- |
| 'Hadspen Hawk' | Medium | Unknown | Pale-Lavender | August to October | Smith, Eric & British Hosta and Hemerocallis Society | .1988 |
| 'Hadspen Heron' | Medium | Unknown | Pale-Lavender | July into August | Smith, Eric & Aden, Paul | .1976 |
| 'Hadspen Nymphae' | Large | Unknown | - | - | Unknown | --NR-- |
| 'Hadspen Pink' | Medium | Unknown | Pale-Lavender | July into August | Smith, Eric & British Hosta and Hemerocallis Society | .1988 |
| 'Hakutei' | Medium | Unknown | - | - | Unknown | --NR-- |
| 'Halcyon' | Small | Hybrid | Pale-Lavender | July into August | Smith, Eric & The American Hosta Society | .1988 |
| 'Halcyon Harmony' | Small | Hybrid | Pale-Lavender | July into August | Treichel, Bernie | .2000 |
| 'Hallelujah' | Medium | Hybrid | Med-Lavender | June into July | Zilis, Mark | .2010 |
| 'Hallie's Honor' | Giant | Hybrid | Near-White | June | Maroushek, Lillian | .1999 |
| 'Happiness' | Medium | Unknown | Pale-Lavender | July into August | Smith, Eric & British Hosta and Hemerocallis Society | .1988 |
| 'Happy Hearts' | Medium | Hybrid | Pale-Lavender | July | Fisher, Eunice V. | .1973 |
| 'Harbor Master' | Large | Unknown | - | - | Unknown | --NR-- |
| 'Harmony' | Small | Unknown | Light-Purple | August | Smith, Eric & Aden, Paul | .1976 |
| 'Harrison' | Giant | Unknown | Pale-Lavender | July | Harrison, Dr Jamison & Ruh, Peter | .1987 |
| 'Hauser Blue Leaf' | Small | Unknown | - | - | Rocknell Nursery | --NR-- |
| 'Headliner' | Giant | Hybrid | Near-White | June | Fisher, Eunice V. & The American Hosta Society | .1986 |
| 'Heart of Chan' | Medium | Hybrid | Pale-Lavender | July | Owens, Clarence | .1987 |
| 'Heart Throb' | Medium | Unknown | Pale-Lavender | June | Anderson, Kenneth | .1982 |
| 'Heartleaf' | Large | Hybrid | Pale-Lavender | July | Fisher, Eunice V. | .1971 |
| 'Hearts in Motion' | Medium | Hybrid | - | July into August | Dean, Don | .2016 |
| 'Heavenly Angel' | Large | Sport | Near-White | June into July | Unknown | --NR-- |
| 'Heavenly Green' | Medium | Sport | Near-White | July into August | Kulpa, John | .1997 |
| 'Heavy Duty' | Large | Hybrid | Pale-Lavender | June into July | de Rooij, Piet | .2013 |
| 'Heavy Metal' | Large | Hybrid | Near-White | June | Stallcop, Jean & Simpers, Lucille | .1993 |
| 'Hebe Blue' | Small | Unknown | Pale-Lavender | July into August | Benedict, Dr Ralph (Herb) & Kuenster, Rod | .2010 |
| 'Helen Doriot' | Large | Hybrid | Near-White | June into July | Reath, David | .1982 |
| 'Helen Field Fischer' | Medium | Unknown | Pale-Lavender | July | Minks, Eldren | .1970 |
| 'Henry Rohr' | Large | Unknown | - | - | Benedict, Dr Ralph (Herb) | --NR-- |
| 'Her Eyes Were Blue' | Medium | Hybrid | Near-White | July into August | Dean, Don | .2008 |
| 'Herb Altman' | Large | Hybrid | Near-White | July | Zolock, Steve & Zolock, Sarah | .2002 |
| 'Hercules' | Giant | Hybrid | - | July | Goffery, James & Summers, Alex | --NR-- |
| 'Herkules' | Giant | Unknown | Med-Lavender | July | Klose, Heinz & Ruh, Peter & Ruh, Jean | .2003 |
| 'Hideko's Pick' | Large | Unknown | Near-White | July | Dean, Don | --NR-- |
| 'High Impact' | Large | Hybrid | Med-Lavender | June into July | Gilligan, Madelon | .2013 |
| 'High Tide' | Medium | Hybrid | Pale-Lavender | August to October | Hansen, Hans | .2005 |
| 'High, Wide, and Handsome' | Giant | Hybrid | Near-White | June into July | Elslager, Ed | .2003 |
| 'Hillbilly Blues' | Large | Hybrid | Pure-White | September | Avent, Tony | .1999 |
| 'Hillbilly Mountain' | Large | Unknown | - | July into August | Schmidt, Bevie | .2009 |
| 'Hime Murasaki' | - | Unknown | - | - | Unknown | --NR-- |
| 'Hime Tokudama' | Small | Hybrid | Pale-Lavender | July | Lantis, Clarence & Ruh, Peter | .2002 .2018 |
| 'Hirao Zeus' | Large | Sport | Near-White | June into July | Hirao, Shuichi & Ruh, Peter | .1997 |
| 'Hishaku' | Medium | Unknown | - | - | Hansen, Hans | --NR-- |
| 'Hoarfrost' | Giant | Hybrid | Near-White | June into July | Fisher, Eunice V. & The American Hosta Society | .1986 |
| 'Hogyoku' | - | Unknown | Light-Purple | - | Unknown | --NR-- |
| 'Holar Dragon Rider' | Large | Hybrid | - | - | Van Keer, Ronny | --NR-- |
| 'Holar Flying Saucer' | Large | Hybrid | - | - | Van Keer, Ronny | --NR-- |
| 'Holar Glacier Walk' | Large | Hybrid | - | - | Van Keer, Ronny | --NR-- |
| 'Holar Ice Empress' | Giant | Hybrid | Pale-Lavender | July | Van Keer, Ronny | --NR-- |
| 'Holar Purple Glacier' | Medium | Hybrid | - | - | Van Keer, Ronny | --NR-- |
| 'Holar Smoky Water' | Medium | Hybrid | - | - | Van Keer, Ronny | --NR-- |
| 'Holy Smokes!' | Large | Unknown | - | July into August | Schwarz, Jim & Schwarz, Karen | .2015 |
| 'Homespun' | Medium | Hybrid | - | - | Livingston, Ron | --NR-- |
| 'Hometown Hero' | Medium | Hybrid | Pure-White | July into August | Stegeman, Bev & Stegeman, Dave | .2014 |
| 'Honey Hill Blue Blood' | Large | Unknown | Pale-Lavender | August to September | Erb, Marsha Axmear | .2003 |
| 'Honey Hill Piece o' Pie' | Large | Unknown | Pale-Lavender | August to September | Erb, Marsha Axmear | .2003 |
| 'Honey Hill Pinking Shears' | Medium | Unknown | - | July into August | Erb, Marsha Axmear | .2003 |
| 'Honey Hill Pledge Allegiance' | Giant | Unknown | Med-Lavender | July into August | Erb, Marsha Axmear | .2003 |
| 'Honey Hill Teardrop' | Small | Unknown | - | - | Erb, Marsha Axmear | --NR-- |
| 'Honey Hill Wayward Heart' | Medium | Unknown | Med-Lavender | June into July | Erb, Marsha Axmear | .2003 |
| 'Honeysong Blue' | Large | Unknown | - | - | Summers, Alex | --NR-- |
| 'Honeysong Blue and Gold' | Large | Sport | Pale-Lavender | July into August | Summers, Alex | --NR-- |
| 'Hoosier Hysteria' | Medium | Unknown | - | - | Goodwin, Randy | .2014 |
| 'Hopewell' | Medium | Unknown | Near-White | June | Wade, Van | --NR-- |
| 'Horse of a Different Color' | Medium | Unknown | Light-Purple | July | Goodwin, Randy | .2019 |
| 'Hosta College' | Small | Unknown | - | - | Unknown | --NR-- |
| 'Hotcakes' | Small | TC Sport | Near-White | July | Zilis, Mark | .2009 |
| 'Housatonic' | Large | Unknown | Near-White | June | Payne, Henry | .1976 |
| 'Hovercraft' | Large | Hybrid | Near-White | July | Beilstein, Doug & Beilstein, Mardy | --NR-- |
| 'Huckleberry Grin' | Giant | Unknown | Near-White | - | Carlson, Monty & Carlson, Julie | --NR-- |
| 'Hugs and Kisses' | Medium | Hybrid | Near-White | June into July | Seaver, Mildred | --NR-- |
| 'Humpback Whale' | Giant | Unknown | Near-White | June into July | Seaver, Mildred & Seaver, Charles | .2012 |
| 'Huron' | Medium | Unknown | Near-White | June into July | Wade, Van | .2007 |
| 'Huron Blue' | Large | Hybrid | Near-White | June into July | Banyai, Pauline & Benedict, Dr Ralph (Herb) | .1990 |
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