N
- Najas flexilis (N)
- Najas gracillima (N)
- Najas guadalupensis ssp. guadalupensis (N)
- Najas marina (N)
- Najas minor (I)
- Napaea dioica (N)
- Narcissus × incomparabilis (I)
- Narcissus jonquilla (I)
- Narcissus × medioluteus (I)
- Narcissus poeticus (I)
- Narcissus pseudonarcissus (I)
- Nasturtium officinale (I)
- Navarretia intertexta ssp. propinqua (N)
- Nelumbo lutea (N)
- Nelumbo nucifera (I)
- Neobeckia aquatica (N)
- Neottia cordata var. cordata (N)
- Nepeta cataria (I)
- Neslia paniculata (I)
- Nicandra physalodes (I)
- Nicotiana alata (I)
- Nicotiana glauca (I)
- Nicotiana rustica (I)
- Nicotiana tabacum (I)
- Nigella damascena (I)
- Nothoscordum bivalve (N)
- Nuphar lutea ssp. advena (N)
- Nuphar lutea ssp. variegata (N)
- Nuttallanthus canadensis (N)
- Nymphaea odorata ssp. odorata (N)
- Nymphaea odorata ssp. tuberosa (N)
- Nymphoides peltata (I)
- Nyssa sylvatica (N)
Read more about this topic: Flora Of Ohio