| Cultivar Name | Plant Size | Leaf Color | Variegation | Var Color | Origin | Flower Color | Season | Source | Registered |
| 'Ma Breeder' | Large | Yellow | Streaked | Speckles | Hybrid | Near-White | June into July | Kuenster, Rod | .2008 |
| 'Maddren' | Giant | Blue/Green | - | - | Hybrid | Pale-Lavender | June into July | Gilligan, Madelon | .2012 |
| 'Madison' | Large | Blue/Green | - | - | Hybrid | Pale-Lavender | June into July | Sanford, Matt | .2011 |
| 'Magic Moment' | Medium | Blue/Green | - | - | Unknown | - | June into July | Ward, Dr Dick & Ward, Jane | .2015 |
| 'Magnificence' | Large | Med-Green | Marginal | White | Hybrid | - | - | Livingston, Ron | --NR-- |
| 'Maid in the Shade' | Large | Light-Green | Marginal | Yellow | Hybrid | - | July into August | Husemann, Jim | .2009 |
| 'Majordomo' | Large | Blue/Green | - | - | Unknown | Near-White | August | Deckert, Emile & Deckert, Jane | .2004 |
| 'Mama Bear' | Large | Light-Green | - | - | Hybrid | - | - | Schmidt, Bevie | .2009 |
| 'Mammoth Ears' | Giant | Blue/Green | - | - | Hybrid | - | June into July | Kruer, George | .2009 |
| 'Man on the Moon' | - | Blue/Green | Streaked | White | TC Sport | - | - | Beilstein, Doug & Zilis, Mark | .2009 |
| 'Mañana' | Large | Dark-Green | - | - | Unknown | Near-White | - | Tompkins, Chet & Ruh, Peter & Ruh, Jean | .2001 |
| 'Manfred's Parfait' | Medium | Med-Green | Medial | White | Unknown | - | - | Mondt, Manfred | --NR-- |
| 'Marbled White' | Large | Dark-Green | Marginal | White | Unknown | Pale-Lavender | July | Owens, Clarence & Walek, Kevin | .2009 |
| 'March for Life' | Small | Dark-Green | - | - | Hybrid | Light-Purple | August | Snyder, Ron | .2001 |
| 'Mardi Gras Parade' | Medium | Blue/Green | Streaked | Yellow | Hybrid | Near-White | July | Vaughn, Kevin | --NR-- |
| 'Margaritaville' | Large | Light-Green | Marginal | Dark Green | Unknown | - | - | Meyer, Bill & Brashear, Carol | --NR-- |
| 'Mariachi' | Large | Med-Green | Marginal | Yellow | Sport | Pale-Lavender | August to September | Zilis, Mark | .2010 |
| 'Marie Curie' | Large | Med-Green | - | - | Unknown | Pale-Lavender | July | Hensen, Karel & Ruh, Peter | .2002 |
| 'Marlu's Evelyn Lucile' | Miniature | Light-Green | - | - | Hybrid | Pale-Lavender | July into August | Overhiser, Martin & Stegeman, Bev & Stegeman, Dave | .2014 |
| 'Marnie's Delight' | Medium | Dark-Green | Medial | Yellow | Unknown | Med-Lavender | July into August | Kuenster, Rod | .2006 |
| 'Marshmallow Sky' | Medium | Med-Green | Medial | White | Sport | Med-Lavender | July | Fransen, Marco & Fransen, Joyce | --NR-- |
| 'Martini' | Small | Med-Green | - | - | Hybrid | Light-Purple | July | Zilis, Mark | .2009 |
| 'Mary Scholl' | Large | Med-Green | Medial | Yellow | Sport | Pale-Lavender | June | Lamlein, Robert | .1999 |
| 'Maui Blue Surf' | Medium | Blue/Green | Streaked | Yellow | Unknown | - | June into July | Elslager, Ed | .2004 |
| 'Maurice Mason' | Miniature | Med-Green | - | - | Unknown | - | July into August | Mason, Maurice & Goodwin, Randy | .2013 |
| 'Me and My Shadow' | Medium | Blue/Green | Medial | Green | TC Sport | Near-White | July | Schwarz, Jim | .2003 |
| 'Memories' | Small | Med-Green | Streaked | Green | Hybrid | Light-Purple | August to September | Klose, Heinz & Ruh, Peter | .2002 .2018 |
| 'Metallica' | Medium | Blue/Green | - | - | Hybrid | Med-Lavender | August | Lachman, Wm & Lachman, Eleanor | .1991 |
| 'Meteor Shower' | Medium | Med-Green | Streaked | White | Hybrid | Med-Lavender | July into August | Elchuk, Kevin & Elchuk, Olga | .2015 |
| 'Michael's Mud Pie' | Large | Med-Green | - | - | Unknown | - | June | Markland, Sandie | .2002 |
| 'Michigan Marvel' | Medium | Med-Green | Marginal | Yellow | Unknown | - | - | Livingston, Ron | --NR-- |
| 'Midnight Dream' | Giant | Blue/Green | - | - | Unknown | - | - | Hackbarth, Robert | .2015 |
| 'Midnight Mistress' | Large | Dark-Green | Streaked | Yellow | Sport | Med-Lavender | July into August | Hackbarth, Robert | .2015 |
| 'Midnight Rain' | Large | Dark-Green | - | - | Unknown | - | - | Dalton, Jim & Dalton, Meg | --NR-- |
| 'Midori Iwa' | Medium | Dark-Green | - | - | Sport | Light-Purple | August to September | Unknown | --NR-- |
| 'Midsummer Night's Green' | Large | Dark-Green | - | - | Hybrid | Med-Lavender | July into August | Goodwin, Randy | .2006 |
| 'Midwest Green' | Large | Med-Green | - | - | Sport | Pale-Lavender | July | Zilis, Mark | --NR-- |
| 'Midwest Majesty' | Giant | Yellow | - | - | Sport | Med-Lavender | July | Minks, Eldren | .1983 |
| 'Mighty Min' | Miniature | Med-Green | - | - | Hybrid | Pale-Lavender | June into July | Gilligan, Madelon | .2013 |
| 'Mighty Mite' | Small | Med-Green | - | - | Hybrid | Med-Lavender | August to September | Dean, Don | .2004 |
| 'Mildred's Smile' | Medium | Yellow | - | - | Hybrid | Near-White | July | Nyikos, Frank | .2007 |
| 'Milk and Honey' | Large | Med-Green | Marginal | White | Sport | Pale-Lavender | August to September | Lynch, P. | .2003 |
| 'Millard Fillmore' | Large | Med-Green | - | - | Unknown | - | - | Ruh, Peter & Ruh, Jean | .2010 |
| 'Mill's Grand Coup' | Medium | Yellow | - | - | Unknown | - | - | Sneyers, Rob | --NR-- |
| 'Mill's Stilbon' | Small | Blue/Green | - | - | Unknown | - | - | Sneyers, Rob | --NR-- |
| 'Mingo' | Large | Dark-Green | - | - | Unknown | Pale-Lavender | July | Wade, Van | .2007 |
| 'Mini Skirt' | Small | Dark-Green | Marginal | White | Sport | Pale-Lavender | June into July | Martinez, Maria & Walters Gardens | .2013 |
| 'Minnesota Nice' | Medium | Dark-Green | Medial | Yellow | Sport | Med-Lavender | July | Snyder, Ron | .1997 |
| 'Minnesota Wild' | Large | Dark-Green | Marginal | White | Hybrid | Med-Lavender | July into August | Carlson, Monty & Carlson, Julie | .2013 |
| 'Mint Chip' | Medium | Med-Green | - | - | Hybrid | Pale-Lavender | June into July | Shadrack, Mike | .2011 |
| 'Mint Condition' (Carlson) | Large | Med-Green | Marginal | White | Unknown | Med-Lavender | June into July | Carlson, Monty & Carlson, Julie | .2013 |
| 'Minutini' | Miniature | Light-Green | - | - | Hybrid | Light-Purple | August | Zilis, Mark | .2009 |
| 'Miracle Lemony' | Medium | Dark-Green | - | - | Hybrid | Yellow | August to September | Sugita, Hajime | --NR-- |
| 'Mirth' | Small | Light-Green | Marginal | Green | Hybrid | Med-Lavender | - | Matsubayashi, Nagao & Ruh, Peter & Ruh, Jean | .2013 |
| 'Miss Ellie Fish' | Large | Yellow | - | - | Unknown | - | - | Hackbarth, Robert | .2015 |
| 'Miss Halley' | Medium | Blue/Green | Medial | Yellow | Sport | Pale-Lavender | July into August | Jones, Leonard | .2003 |
| 'Miss Mitzi' | Medium | Dark-Green | Marginal | White | Hybrid | Med-Lavender | June into July | Schroeder, Bob & Schroeder, Barb & Beilstein, Doug | .2016 |
| 'Miss Shamim' | Large | Light-Green | - | - | Hybrid | Light-Purple | August to September | McHugh, Ed & Wrede, Arthur | .2015 |
| 'Misty May' | Medium | Med-Green | Streaked | Speckles | Hybrid | Med-Lavender | July into August | Kuenster, Rod | .2008 |
| 'Misty Regal' | Giant | Med-Green | Medial | Yellow | Sport | Med-Lavender | July | Stratton, John & Stratton, Elizabeth | .1996 |
| 'Miyazaki' | Small | Med-Green | Medial | White | Hybrid | - | August to September | Zilis, Mark | .2010 |
| 'Modern Dance' | Medium | Blue/Green | Streaked | White | Hybrid | Med-Lavender | August to September | Van Eechaute, Danny | .2014 |
| 'Mojito' | Large | Med-Green | - | - | TC Sport | Pale-Lavender | August | Zilis, Mark | .2009 |
| 'Mom's Girl' | Large | Dark-Green | Streaked | Yellow | Unknown | - | - | Elslager, Ed | .2003 |
| 'Monet' (Zilis) | Small | Blue/Green | Medial | Green | TC Sport | Near-White | July into August | Zilis, Mark | .2011 |
| 'Monochrome' | Miniature | Yellow | - | - | TC Sport | Light-Purple | July into August | Zilis, Mark | .2011 |
| 'Montreal Blue Ice Storm' | Giant | Blue/Green | - | - | Hybrid | Pale-Lavender | June into July | Wade, Van | .2007 |
| 'Monty Python' | Medium | Yellow | Streaked | White | TC Sport | Pale-Lavender | July | Zilis, Mark | .2009 |
| 'Moolah' | Miniature | Dark-Green | Marginal | Yellow | Hybrid | Pale-Lavender | June into July | Goodwin, Randy | .2013 |
| 'Moon Dance' (Dean) | Medium | Yellow | Marginal | White | Hybrid | Pale-Lavender | June into July | Dean, Don | .2011 |
| 'Moon Maiden' | Large | Yellow | - | - | Hybrid | Pale-Lavender | June into July | Nyikos, Frank | .2011 |
| 'Moonrise' | Large | Light-Green | Marginal | Yellow | Hybrid | - | June into July | Ward, Dr Dick & Ward, Jane | .2010 |
| 'Mosel' | Medium | Med-Green | - | - | Unknown | Med-Lavender | - | Klose, Heinz & Ruh, Peter & Ruh, Jean | .2008 |
| 'Moulin Rouge' | Medium | Dark-Green | Medial | White | Sport | Pale-Lavender | July into August | Van Eechaute, Danny | .2010 |
| 'Mount Olympus' | Large | Med-Green | - | - | Sport | Pale-Lavender | July | Malloy, Alex | --NR-- |
| 'Mountain Pride' | Giant | Med-Green | - | - | Unknown | - | July into August | Benedict, Dr Ralph (Herb) & Kuenster, Rod | .2010 |
| 'Mouse Capades' | Small | Blue/Green | Marginal | White | Sport | Light-Purple | June into July | Mortko, Rob | .2013 |
| 'Munchkin Fire' | Miniature | Light-Green | - | - | Unknown | Med-Lavender | July | Goodwin, Randy | .2009 |
| 'Murphy's Golden Marge' | Medium | Yellow | - | - | Unknown | Pure-White | June into July | Zolock, Steve & Zolock, Sarah | .2001 |
| 'Mustang' | Small | Med-Green | - | - | Sport | Med-Lavender | June into July | Malloy, Alex | .2002 |
| 'My Gal Sal' | Medium | Yellow | Streaked | White | Sport | - | July into August | Freeman, Franc | .2009 |
| 'My Girl' | Medium | Med-Green | Marginal | White | Unknown | Pale-Lavender | June into July | Schwarz, Jim | .2012 |
| 'My Mom' | Medium | Dark-Green | Streaked | Yellow | Hybrid | Near-White | June | Kuenster, Rod | .2008 |
| 'My Old Flame' | Small | Light-Green | Marginal | White | Hybrid | Pale-Lavender | June | Ward, Dr Dick & Ward, Jane | .2012 |
| 'My Yuma' | Large | Dark-Green | - | - | Unknown | Med-Lavender | - | Livingston, Ron | --NR-- |
| 'Mystery Mom' | Large | Blue/Green | Streaked | Speckles | Unknown | - | July into August | Elslager, Ed | .2005 |
|