Plants
- manzanitaarctostaphylos
- Manzano Pepper 'Orange'Capsicum pubescens
- MapleAcer campbelli ssp. flabellatum yunnanense
- Mapleleaf ViburnumViburnum acerifolium
- Măr (Apple tree) 'Golden Delicious'Malus domestica 'Golden Delicious'
- Marguerite StandardArgyranthemum
- Mariesi Variegated HydrangeaHydrangea macrophylla 'Mariesi'
- MarigoldMarigold French Aurora Fire
- Marigold Orange Hawaii
- Marigold Petite Mix
- Marigold, 'Fiesta Gitana'Calendula officinalis 'Fiesta Gitana'
- Marketmore 76 Slicing Cucumbers
- Marleen SnowberrySymphoricarpos x doorenbossil 'Ariso' PPAF
- Marrow Cucurbita pepo
- Marsh CinquefoilPotentilla palustris
- Marsh MarigoldCaltha Palustris
- Marsh Marigold, Kingcup (Wildlife)Caltha palustris (wildflower)
- Marsh Orchid, Spotted OrchidDactylorhiza maderensis, syn D. foliosa
- Marsh PennywortHydrocotyle vulgaris
- Marsh-mallowAlthaea officinalis
- Martagon LilyLilium martagon
- Mary JaneCannabis Sativa
- Masdevallia OrchidMasdevallia coccinea
- Masterwort, 'Sunningdale'Astrantia major 'Sunningdale'
- Matthiola Incana Ten Week
- May HawthornCrataegus laevigata
- May LilyMaianthemum bifolium
- May-ApplePodophyllum peltatum
- Maysville DaisyCoreopsis Auriculata 'Nana'
- Mazus reptans 'Purple'Mazus reptans 'Purple'
- Meadow anemoneAnemone canadensis
- Meadow Blazingstar LiatrisLiatris ligulistylis
- Meadow ButtercupRanunculus acris
- Meadow Crane's-billGeranium pratense
- Meadow PhloxPhlox maculata