| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Mammoth Ears' | Giant | Blue/Green | - | - | Hybrid | - | June into July | Kruer, George | .2009 |
| 'Marlu's Clayton' | Large | Yellow | - | - | Hybrid | Near-White | June into July | Overhiser, Martin | .2014 |
| 'Marlu's Eliza Jane' | Small | Dark-Green | - | - | Hybrid | Med-Lavender | August | Overhiser, Martin | .2014 |
| 'Marlu's Evelyn Lucile' | Miniature | Light-Green | - | - | Hybrid | Pale-Lavender | July into August | Overhiser, Martin & Stegeman, B & D | .2014 |
| 'Marlu's Marla Jean' | Miniature | Light-Green | - | - | Hybrid | Pale-Lavender | July into August | Overhiser, Martin | .2014 |
| 'Marlu's Marshall' | Large | Blue/Green | - | - | Hybrid | Near-White | June into July | Overhiser, Martin | .2014 |
| 'Marlu's Ronald Wayne' | Medium | Light-Green | - | - | Hybrid | Med-Lavender | July into August | Overhiser, Martin | .2014 |
| 'Marýke Lokike' | Medium | Blue/Green | - | - | Hybrid | - | June into July | Lokies, Martin | .2008 |
| 'Memories' | Small | Med-Green | Streaked | Green | Hybrid | Light-Purple | August to September | Klose, Heinz & Ruh, Peter | .2002 .2018 |
| 'Merci Marci' | Small | Blue/Green | Marginal | White | Unknown | - | July into August | Asch, Stuart | .2008 |
| 'Midnight Mistress' | Large | Dark-Green | Streaked | Yellow | Nat-Sport | Med-Lavender | July into August | Hackbarth, Robert | .2015 |
| 'Mirth' | Small | Light-Green | Marginal | Green | Hybrid | Med-Lavender | - | Matsubayashi, N. & Ruh, Peter & Jean | .2013 |
| 'Miss Ellie Fish' | Large | Yellow | - | - | Unknown | - | - | Hackbarth, Robert | .2015 |
| 'Misty May' | Medium | Med-Green | Streaked | Speckles | Hybrid | Med-Lavender | July into August | Kuenster, Rod | .2008 |
| 'Miyazaki' | Small | Med-Green | Medial | White | Hybrid | - | August to September | Zilis, Mark | .2010 |
| 'Moon Dance' (Dean) | Medium | Yellow | Marginal | White | Hybrid | Pale-Lavender | June into July | Dean, Don | .2011 |
| 'Mop Top' | Miniature | Dark-Green | - | - | Hybrid | Pure-White | - | Beilstein, Doug & Mardy | .2009 |
| 'Mountain Pride' | Giant | Med-Green | - | - | Unknown | - | July into August | Benedict, Dr R. (Herb) & Dorothy & Kuenster, Rod | .2010 |
| 'Munchkin Fire' | Miniature | Light-Green | - | - | Unknown | Med-Lavender | July | Goodwin, Randy | .2009 |
| 'My Man Mark' | Giant | Med-Green | - | - | Hybrid | - | - | Schmidt, Bevie | .2009 |
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