Ononis repens
Common Restharrow
Ononis spinosa
Spiny Restharrow
Ophioglossum vulgatum
Adder's-tongue
Ophioparma ventosa
Blood-spot Lichen
Ophrys apifera
Bee Orchid
Ophrys fuciflora
Late Spider-orchid
Ophrys insectifera
Fly Orchid
Ophrys insectifera x apifera
Ophrys sphegodes
Early Spider-orchid
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
Oreopteris limbosperma
Lemon-scented Fern
Origanum vulgare
Wild Marjoram
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