| Scientific Name |
Common Name(s) |
Plant Category |
Image |
| Nymphaea 'Sioux' |
Sioux |
Water Garden |
 |
| Nymphaea 'Sirius' |
Sirius |
Water Garden |
 |
| Nymphaea 'Splendida' |
Splendida |
Water Garden |
 |
| Nymphaea 'St. Louis Gold' |
St. Louis Gold |
Water Garden |
 |
| Nymphaea 'St. Louis' |
St. Louis |
Water Garden |
 |
| Nymphaea 'Starbright' |
Starbright |
Water Garden |
 |
| Nymphaea 'Sultan' |
Sultan |
Water Garden |
 |
| Nymphaea 'Texas Dawn' |
Texas Dawn |
Water Garden |
 |
| Nymphaea 'Tina' |
Tina |
Water Garden |
 |
| Nymphaea 'Venus' |
Venus |
Water Garden |
 |
| Nymphaea 'Virginalis' |
Virginalis |
Water Garden |
 |
| Nymphaea 'Virginia' |
Virginia |
Water Garden |
 |
| Nymphaea 'William Falconer' |
William Falconer |
Water Garden |
 |
| Nymphaea 'Yellow Dazzler' |
Yellow Dazzler |
Water Garden |
 |
| Nymphaea colorata |
Blue Pigmy, Colorata |
Water Garden |
 |
| Nymphaea x marliacea 'Carnea' |
Carnea |
Water Garden |
 |
| Nymphaea x marliacea 'Chromatella' |
Chromatella |
Water Garden |
 |
| Nymphoides pelatum |
Floating heart |
Water Garden |
 |
| Nyssa aquatica |
Water tupelo |
Trees |
 |
| Nyssa ogeche |
Ogeechee lime, Ogeechee tupelo |
Trees |
 |
| Nyssa sinensis |
Chinese tupelo |
Trees |
 |
| Nyssa sylvatica |
Black gum, Black tupelo, Sour gum |
Native Plants, Trees |
 |
| Ocimum basilicum |
Sweet basil |
Edible Plants, Herbs |
 |
| Odontonema strictum |
Firespike |
Annuals |
 |
| Oenothera biennis |
Evening primrose |
Perennials, Wildflowers |
 |
| Oenothera fruticosa |
Sundrops |
Native Plants, Perennials |
 |
| Oenothera speciosa |
Showy evening primrose |
Perennials |
 |
| Oenothera tetragona |
Sundrops |
Perennials, Wildflowers |
 |
| Omphalodes linifolia |
Navelwort |
Annuals |
 |
| Omphalotus olearius (Clitocybe illudens) |
Jack-O-Lantern |
Poisonous Plants |
 |
| Onoclea sensibilis |
Bead fern, Sensitive fern |
Ferns, Native Plants |
 |
| Ophiopogon jaburan vittata |
Snakebeard, White lilyturf |
Groundcover |
|
| Ophiopogon japonicus |
Mondo grass |
Groundcover |
 |
| Ophiopogon japonicus 'Nana' |
Dwarf mondo grass |
Groundcover |
 |
| Opuntia spp. |
Rabbit ears cactus, prickly pear cactus |
Poisonous Plants |
 |
| Origanum majorana |
Sweet marjoram |
Edible Plants, Herbs |
 |
| Origanum vulgare |
Oregano |
Edible Plants, Herbs |
 |
| Ornithogalum |
Star of Bethlehem |
Summer Bulbs |
 |
| Ornithogalum umbellatum |
Star of Bethlehem |
Perennial Bulbs, Spring Bulbs |
 |
| Ornithogalum umbellatum, O. thrysoides |
Ornithogalum, Star-of-Bethlehem |
Poisonous Plants |
|
| Orontium aquaticum |
Golden club |
Poisonous Plants, Water Garden, Wildflowers |
 |
| Osmanthus americanus |
Devilwood, Wild olive |
Native Plants, Shrubs, Trees |
 |
| Osmanthus delavayi |
Delavay teaolive |
Shrubs |
 |
| Osmanthus fragrans |
Fragrant tea olive, Sweet osmanthus |
Shrubs |
 |
| Osmanthus heterophyllus |
False holly, Holly osmanthus, Holly tea olive |
Shrubs |
 |
| Osmanthus x burkwoodii |
Burkwood osmanthus |
Shrubs |
 |
| Osmanthus x fortunei |
Fortune's osmanthus, Fortune's tea olive |
Shrubs |
 |
| Osmunda cinnamomea |
Cinnamon fern |
Ferns |
 |
| Osmunda claytoniana |
Clayton's fern, Interrupted fern |
Ferns |
 |
| Osmunda regalis |
Flowering fern, Royal fern |
Ferns |
 |
