Oenothera biennis
Small-flowered Evening-primrose
Onobrychis viciifolia
Sainfoin
Ononis reclinata
Small Restharrow
Ononis repens
Common Restharrow
Ononis spinosa
Spiny Restharrow
Ophrys apifera
Bee Orchid
Origanum vulgare
Wild Marjoram
Ornithogalum pyrenaicum
Spiked Star-of-Bethlehem
Ornithogalum umbellatum
Star-of-Bethlehem
Orobanche caryophyllacea
Bedstraw Broomrape
Orobanche hederae
Ivy Broomrape
Orobanche minor
Common Broomrape
Orobanche rapum-genistae
Greater Broomrape
Orthilia secunda
Serrated Wintergreen
Oxybasis glauca
Oak-leaved Goosefoot
Papaver lecoqii
Yellow-juiced Poppy
Parentucellia viscosa
Yellow Bartsia
Parietaria judaica
Pellitory-of-the-wall
Paris quadrifolia
Herb-paris
Parnassia palustris
Grass-of-Parnassus
Pastinaca sativa
Wild Parsnip
Paulownia tomentosa
Foxglove-tree
Pentaglottis sempervirens
Green Alkanet
Persicaria amphibia
Amphibious Bistort