Nerine bowdenii
Cape Flower
Nerine flexuosa
Nerium oleander
Oleander
Neustanthus phaseoloides
Tropical Kudzu
Nicandra physalodes
Apple-of-Peru
Nigritella nigra
Black Vanilla Orchid
Noccaea caerulescens
Alpine Penny-cress
Nonea lutea
Yellow Nonea
Nothofagus alpina
Rauli
Nothoscordum borbonicum
Honeybells
Nuphar lutea
Yellow Water-lily
Nymphaea alba
White Water-lily
Nymphaea capensis
Cape Blue Waterlily
Nymphaea lotus
Egyptian lotus
Nymphaea x marliacea
Coloured Water-lily
Nymphoides peltata
Fringed Water-lily
Nypta fruticans
Nipa Palm
Ochna serrulata
Small-leaved Plane
Ocimum americanum
American Basil
Ocinum americanum
American Basil
Odontites vernus
Red Bartsia
Oenanthe aquatica
Fine-leaved Water-dropwort
Oenanthe crocata
Hemlock Water-dropwort
Oenanthe fistulosa
Tubular Water-dropwort
Oenanthe lachenalii
Parsley Water-dropwort
Oenanthe pimpinelloides
Corky-fruited Water-dropwort
Oenanthe silaifolia
Narrow-leaved Water-dropwort
Oenothera biennis
Small-flowered Evening-primrose
Oenothera glazioviana
Large-flowered Evening-primrose
Oenothera stricta
Fragrant Evening-primrose
Olearia macrodonta
New Zealand Holly
Onobrychis viciifolia
Sainfoin
Ononis arvensis
Ononis reclinata
Small Restharrow
Ononis repens
Common Restharrow
Ononis spinosa
Spiny Restharrow
Ophiopogon jaburan
Giant Lilyturf
Ophrys apifera
Bee Orchid
Ophrys fuciflora
Late Spider-orchid
Ophrys insectifera
Fly Orchid
Ophrys insectifera x apifera
Ophrys sphegodes
Early Spider-orchid
Opuntia cochenillifera
Cochineal Cactus
Opuntia ficus-indica
Prickly Pear
Opuntia microdasys
Angel's-wings
Orchis mascula
Early-purple Orchid
Orchis militaris
Military Orchid
Orchis purpurea
Lady Orchid
Orchis simia
Monkey Orchid
Orchis x angusticruris
Lady#Orchid#/ Monkey#Orchid#hybrid
Origanum vulgare
Wild Marjoram
Ornithogalum nutans
Drooping Star-of-Bethlehem
Ornithogalum pyrenaicum
Spiked Star-of-Bethlehem
Ornithogalum umbellatum
Star-of-Bethlehem
Ornithopus perpusillus
Bird's-foot
Orobanche caryophyllacea
Bedstraw Broomrape
Orobanche hederae
Ivy Broomrape
Orobanche minor
Common Broomrape
Orobanche picridis
Oxtongue Broomrape
Orobanche rapum-genistae
Greater Broomrape
Orontium aquaticum
Golden-club
Orthilia secunda
Serrated Wintergreen
Osmoxylon lineare
Green Aralia
Oxalis acetosella
Wood-sorrel
Oxalis articulata
Pink-sorrel
Oxalis corniculata
Creeping Woodsorrel
Oxalis incarnata
Pale Pink-sorrel
Oxalis triangularis
False Shamrock
Oxybasis glauca
Oak-leaved Goosefoot
Oxybasis rubra
Red Goosefoot