No. | Cultivar Name | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
1
| 'Oberland Spring Air' | Med-Green | Medial | White | Sport | Pure-White | July to August | Rank, Stefan | .2013 |
2
| 'Ocean's Fury' | Blue/Green | | | Hybrid | Unknown | Unknown | Rawson, Don | --NR-- |
3
| 'Ogon Sudare' | Yellow | | | Unknown | Pale-Lavender | July | Unknown & Ruh, Peter | .2002 .2018 |
4
| 'Ohh! Blue Otto' | Blue/Green | | | Unknown | Unknown | Unknown | Schulz, Ed | .2009 |
5
| 'Ohh! Ludell' | Yellow | | | Unknown | Unknown | Unknown | Schulz, Ed | .2009 |
6
| 'Ohh! Powder River Blue' | Blue/Green | | | Unknown | Near-White | June to July | Schulz, Ed | .2020 |
7
| 'Okazaki' | Med-Green | | | Hybrid | Med-Lavender | August to September | Sugita, Hajime & Ruh, Peter & Ruh, Jean | .2002 |
8
| 'Okobaji' | Blue/Green | | | Unknown | Unknown | Unknown | Tompkins, Chet & Ruh, Peter & Ruh, Jean | .2008 |
9
| 'Orange Slices' | Yellow | | | TC Sport | Pale-Lavender | July to August | Zilis, Mark | .2003 |
10
| 'Over the Rainbow' | Med-Green | Streaked | Speckles | Hybrid | Near-White | June to July | Elslager, Ed | .2005 |
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