Orchis mascula
Early-purple Orchid
Orchis militaris
Military Orchid
Orchis x angusticruris
Lady#Orchid#/ Monkey#Orchid#hybrid
Oreopteris limbosperma
Lemon-scented Fern
Ornithogalum pyrenaicum
Spiked Star-of-Bethlehem
Ornithopus perpusillus
Bird's-foot
Orthilia secunda
Serrated Wintergreen
Osmoxylon lineare
Green Aralia
Osmunda regalis
Royal Fern
Oxalis acetosella
Wood-sorrel
Oxybasis glauca
Oak-leaved Goosefoot
Oxybasis rubra
Red Goosefoot
Papaver cambricum
Welsh Poppy
Parentucellia viscosa
Yellow Bartsia
Parietaria judaica
Pellitory-of-the-wall
Paris quadrifolia
Herb-paris
Parnassia palustris
Grass-of-Parnassus
Paulownia tomentosa
Foxglove-tree
Pedicularis palustris
Marsh Lousewort
Pentaglottis sempervirens
Green Alkanet
Peperomia pellucida
Pepper Elder
Peperomia polybotrya
Raindrop Peperomia
Persicaria amphibia
Amphibious Bistort
Persicaria hydropiper
Water-pepper