| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Immense' | Giant | Dark-Green | - | - | Hybrid | Near-White | July | Ruh, Peter | .1991 |
| 'Imperial Majesty' | Large | Med-Green | - | - | Hybrid | Pale-Lavender | August | Sellers, Van & Ruh, Peter | .2003 |
| 'Inaho' | Medium | Dark-Green | Streaked | White | Unknown | Light-Purple | August to September | Unknown & Ruh, Peter | .2005 .2018 |
| 'Incognito' | Large | Blue/Green | Marginal | Yellow | Sport | Near-White | July into August | Struhar, Bill | .2006 |
| 'Indian Princess' | Large | Blue/Green | - | - | Hybrid | Near-White | June | Harshbarger, Gretchen & Ruh, Peter | .1998 |
| 'Innovation' | Medium | Dark-Green | - | - | Hybrid | Pure-White | - | Nesmith, Elizabeth & Ruh, Peter | .1996 |
| 'Irische See' | Medium | Blue/Green | - | - | Hybrid | Pale-Lavender | July | Klose, Heinz & Ruh, Peter | .1998 |
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