Hygrocybe psittacina
Parrot Waxcap
Hylotelephium telephium
Orpine
Hymenophyllum tunbrigense
Tunbridge Filmy-fern
Hymenophyllum wilsonii
Wilson's Filmy-fern
Hypericum androsaemum
Tutsan
Hypericum calycinum
Rose-of-Sharon
Hypericum elodes
Marsh St John's-wort
Hypericum hirsutum
Hairy St John's-wort
Hypericum humifusum
Trailing St John's-wort
Hypericum perforatum
Perforate St John's-wort
Hypholoma fasciculare
Sulphur Tuft
Hypochaeris radicata
Cat's-ear
Hypopitys monotropa
Yellow Bird's-nest
Iberis amara
Wild Candytuft
Ilex aquifolium
Holly
Impatiens glandulifera
Indian Balsam
Impatiens noli-tangere
Touch-me-not Balsam
Inachis io
European Peacock Butterfly
Iris foetidissima
Stinking Iris
Iris pseudacorus
Yellow Iris
Isatis tinctoria
Woad
Isoetes lacustris
Quillwort
Jacobaea aquatica
Marsh Ragwort
Jasione montana
Sheep's-bit