| No. | Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
|
1
| 'Oberland Darkness' | Medium | Dark-Green | - | - | Hybrid | - | - | Rank, Stefan | --NR-- |
|
2
| 'Ocean Isle Blue' | Medium | Blue/Green | | | Unknown | | | Chopko, Dave | --NR-- |
|
3
| 'Ocean Isle Tide Line' | Medium | Dark-Green | Medial | White | Unknown | | | Chopko, Dave | --NR-- |
|
4
| 'Ocean Isle Tornado' | Medium | Med-Green | Medial | White | Sport | Med-Lavender | July into August | Chopko, Dave | --NR-- |
|
5
| 'Oceans Away' | Giant | Blue/Green | - | - | Unknown | - | June into July | Hanson, Curt | --NR-- |
|
6
| 'Ogon Amagi Iwa' | Medium | Dark-Green | - | - | Sport | Light-Purple | September | Unknown & Walek, Kevin & The American Hosta Society | .2009 .2018 |
|
7
| 'Ohh! Laurel' | - | Yellow | - | - | Unknown | - | - | Schulz, Ed | .2009 |
|
8
| 'Ohh! Viola' | Medium | Yellow | - | - | Unknown | Near-White | June into July | Schulz, Ed | .2015 |
|
9
| 'Okazaki' | Small | Med-Green | - | - | Hybrid | Med-Lavender | August to September | Sugita, Hajime & Ruh, Peter & Ruh, Jean | .2002 |
|
10
| 'Old Wethersfield' | Large | Dark-Green | | | Unknown | Light-Purple | | Goodenough, Rick | --NR-- |
|
11
| 'Olive Oil' | Medium | Yellow | - | - | Hybrid | Pale-Lavender | - | Dishon, Jim | .1996 |
|
12
| 'Ooshima-jishi' | Medium | Med-Green | Medial | Yellow | Unknown | | | Unknown | --NR-- |
|
13
| 'Osiris Obscure' | Large | Dark-Green | - | - | Unknown | - | - | Fafard, Serge | --NR-- |
|
14
| 'Otter Point' | Large | Med-Green | - | - | Unknown | Med-Lavender | - | Wrede, Arthur | --NR-- |
|
15
| 'Oze' | Miniature | Med-Green | Marginal | Yellow | Unknown | Near-White | August | Unknown | --NR-- |
|