| No. | Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
|
1
| 'Ohh! Amber' | Small | Dark-Green | Marginal | White | Hybrid | Med-Lavender | July to August | Schultz, Ed | .2021 |
|
2
| 'Ohh! Blue Otto' | Small | Blue/Green | | | Unknown | Unknown | Unknown | Schulz, Ed | .2009 |
|
3
| 'Ohh! Ultra Aqua' | Medium | Blue/Green | | | Unknown | Unknown | Unknown | Schulz, Ed | --NR-- |
|
4
| 'OHS Juno' | Medium | Blue/Green | | | Sport | Pale-Lavender | July to August | Ontario Hosta Society | --NR-- |
|
5
| 'Okobaji' | Small | Blue/Green | | | Unknown | Unknown | Unknown | Tompkins, Chet & Ruh, Peter & Ruh, Jean | .2008 |
|
6
| 'Omatsu-san Nishiki' | Small | Light-Green | | | Unknown | Light-Purple | Unknown | Ruh, Peter | .2002 .2018 |
|
7
| 'Orange Joy' | Small | Yellow | | | Hybrid | Light-Purple | July | Carpenter, Kate | .1979 |
|
8
| 'Outer Space' | Small | Light-Green | Marginal | White | Sport | Pale-Lavender | July | Malloy, Alex | .2003 |
|
9
| 'Outrageous' | Large | Dark-Green | Streaked | White | Hybrid | Pure-White | July | Benedict, Dr Ralph (Herb) & Walek, Kevin & The American Hosta Society | .2009 |
|
10
| 'Over the Moon' | Medium | Med-Green | Marginal | White | Hybrid | Unknown | June to July | Ward, Dr Dick & Ward, Jane | .2010 |
|
11
| 'Over the Waves' | Medium | Blue/Green | | | Unknown | Unknown | August to September | Benedict, Dr Ralph (Herb) & Kuenster, Rod | .2010 |
|