No. | Cultivar Name | Source | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Registered |
1
| 'Kanagashi' | George, Arthur | Unknown | Unknown | | | Unknown | Unknown | Unknown | --NR-- |
2
| 'Katherine Lewis' | Lewis, Alan | Small | Yellow | Marginal | Blue-Green | Hybrid | Pale-Lavender | July to August | --NR-- |
3
| 'Kath's Gold' | Dryden, Kath | Small | Yellow | | | Unknown | Unknown | Unknown | --NR-- |
4
| 'Kayak' | Black, Gwen & Ruh, Peter | Large | Blue/Green | | | Unknown | Pale-Lavender | July | .1999 |
5
| 'Kingfisher' | Smith, Eric & British Hosta and Hemerocallis Society | Medium | Blue/Green | | | Unknown | Pale-Lavender | August to September to October | .1988 |
6
| 'Kite' | Smith, Eric & British Hosta and Hemerocallis Society | Medium | Blue/Green | | | Unknown | Unknown | Unknown | .1988 |
7
| 'Knaves Green' | Ford, Richard & Ford, Mary | Small | Blue/Green | Streaked | Yellow | Unknown | Unknown | Unknown | --NR-- |
8
| 'Koneko Falls' | Pether, Glen | Large | Yellow | Marginal | Green | Hybrid | Unknown | Unknown | --NR-- |
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