| Marginal Variegation | Plant Size | Leaf Color | Var Color | Origin | Season | Source | Registered |
| 'Ufo' | Giant | Dark-Green | Yellow | Nat-Sport | July into August | Fransen, Marco | --NR-- |
| 'Ugga Bugga' | Small | Blue/Green | White | Unknown | July into August | Goodwin, Randy | .2017 |
| 'Ugly Duckling' | Large | Yellow | White | TC Sport | July | Zilis, Mark & Ruh, Peter | .1999 |
| 'Uju' | Small | Dark-Green | Yellow | Nat-Sport | July into August | Zilis, Mark | .2011 |
| 'Umezawa' | Small | Med-Green | Yellow | Nat-Sport | August to October | Umezawa, Senkichi | --NR-- |
| 'Umi Oba' | Large | Med-Green | Yellow | Hybrid | July | Unknown | --NR-- |
| 'Unbridled Passion' | Medium | Light-Green | White | Hybrid | July into August | Johnson, Greg | .2004 |
| 'Unchained Melody' | Large | Dark-Green | Creamy White | Hybrid | July | Wilkins, Dr Jim | .2000 |
| 'Uncle Fester' | Large | Dark-Green | Yellow | Unknown | - | Meyer, Bill | --NR-- |
| 'Uncle Hirsch' | - | Blue/Green | Yellow | Hybrid | August to September | Graves, Butch | .2008 |
| 'Undulata Albomarginata' | Medium | Med-Green | White | Unknown | July | AHS | .1987 |
| 'Undulata Kifukurin' | Medium | Med-Green | Yellow | Unknown | - | Unknown | --NR-- |
| 'Undulata White Beauty' | Small | Med-Green | White | Unknown | - | Unknown | --NR-- |
| 'Unexpected Pleasure' | Large | Dark-Green | White | Hybrid | July into August | Asch, Stuart | .2000 |
| 'Unforgettable' | Large | Blue/Green | Yellow | Hybrid | July | Kuk, Bob | .1999 |
| 'Uniquely Catawampus' | Small | Med-Green | White | Hybrid | August to September | Rosenberg, Marlene & Miller, Jeff | .2016 |
| 'Unsinkable Molly Brown' | Large | Dark-Green | Green | Nat-Sport | July into August | Postlewaite, Peter | .2013 |
| 'Unstable Mable' | Medium | Med-Green | White | Nat-Sport | - | Unknown | --NR-- |
| 'Unsung Hero' | Medium | Med-Green | Yellow | Nat-Sport | July | Hansen, Hans | --NR-- |
| 'Up to Marc' | - | Light-Green | White | Unknown | - | Unknown | --NR-- |
| 'Uplift' | Small | Yellow | White | Unknown | - | Aden, Paul | --NR-- |
| 'Upper Crust' | Medium | Yellow | Green | TC Sport | July | Zilis, Mark | .2004 |
| 'Uprising' | Medium | Dark-Green | Yellow | Nat-Sport | - | Fransen, Marco & Joyce | --NR-- |
| 'Urashima' | - | Med-Green | White | Unknown | - | Hirose, Yoshimichi | --NR-- |
| 'Ussuri' | Large | Blue/Green | Yellow | Unknown | - | Unknown | --NR-- |
| 'Utsukushigahara Fukurin Oba' | Large | Med-Green | Yellow | Nat-Sport | July | Watanabe, Kenji | --NR-- |
| 'Uzu-no-mai Fukurin' | Miniature | Dark-Green | White | Nat-Sport | August | Unknown | --NR-- |
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