Phalaris arundinacea
Reed Canary-grass
Phalaris canariensis
Canary-grass
Phleum arenarium
Sand Cat's-tail
Phleum bertolonii
Smaller Cat's-tail
Phleum pratense
Timothy
Phormium cookianum
Lesser New Zealand Flax
Phragmites australis
Common Reed
Platanthera bifolia
Lesser Butterfly-orchid
Platanthera chlorantha
Greater Butterfly-orchid
Platanthera x hybrida
Pleione formosana
Pleione
Poa annua
Annual Meadow-grass
Poa compressa
Flattened Meadow-grass
Poa humilis
Spreading Meadow-grass
Poa trivialis
Rough Meadow-grass
Polygonatum multiflorum
Solomon's-seal
Polygonatum odoratum
Angular Solomon's-seal
Polygonatum verticillatum
Whorled Solomon's-seal
Polygonatum x hybridum
Garden Solomon's-seal
Polypogon viridis
Water Bent
Potamogeton coloratus
Fen Pondweed
Potamogeton crispus
Curled Pondweed
Potamogeton lucens
Shining Pondweed
Potamogeton natans
Broad-leaved Pondweed