Hevea brasiliensis
Pará Rubber Tree
Hibiscus tiliaceus
Sea Hibiscus
Hieracium argillaceum
Southern Hawkweed
Hieracium asteridiophyllum
Star-haired Hawkweed
Hieracium attenboroughianum
Attenborough’s Hawkweed
Hieracium breconense
Brecon Hawkweed
Hieracium clivicola
Hill Hawkweed
Hieracium daedalolepioides
Petite-leaved Hawkweed
Hieracium discophyllum
Disc-leaved Hawkweed
Hieracium hypochaeroides
Cat's-ear Hawkweed
Hieracium inspissatum
Crass-leaved Hawkweed
Hieracium neocoracinum
Craig Gleisiad Hawkweed
Hieracium pulchrius
Beautiful Hawkweed
Hieracium repandulare
Repand-leaved Hawkweed
Hieracium reticulatiforme
Reticulate-leaved Hawkweed
Hieracium sabaudum
Autumn Hawkweed
Hieracium sect. Hieracioides
Hieracium sect. Oreadea
Hieracium sect. Sabauda
Hieracium sect. Stelligera
Hawkweed (Stelligera)
Hieracium sp.
Hieracium stenopholidium
Western Hawkweed
Hieracium subbritannicum
Hieracium subminutidens
Llanwrtyd Hawkweed
Hieracium tavense
Tawe Hawkweed
Hippeastrum puniceum
Amaryllis Lily
Hippophae rhamnoides
Sea-buckthorn
Hippuris vulgaris
Mare's-tail
Hirschfeldia incana
Hoary Mustard
Honckenya peploides
Sea Sandwort
Hordeum vulgare
Six-rowed Barley
Hornungia petraea
Hutchinsia
Hottonia palustris
Water-violet
Houttuynia cordata
Fish-plant
Humulus lupulus
Hop
Huperzia selago
Fir Clubmoss
Hyacinthoides non-scripta
Bluebell
Hydrocharis morsus-ranae
Frogbit
Hydrocotyle hirta
Hydrocotyle vulgaris
Marsh Pennywort
Hylotelephium telephium
Orpine
Hymenophyllum tunbrigense
Tunbridge Filmy-fern
Hymenophyllum wilsonii
Wilson's Filmy-fern
Hyophorbe lagenicaulis
Bottle Palm
Hypericum androsaemum
Tutsan
Hypericum elodes
Marsh St John's-wort
Hypericum hirsutum
Hairy St John's-wort
Hypericum humifusum
Trailing St John's-wort
Hypericum maculatum
Hypericum pulchrum
Slender St John's-wort
Hypericum x caesariense
Hypochaeris radicata
Cat's-ear
Hypopitys monotropa
Yellow Bird's-nest
Ilex aquifolium
Holly
Illecebrum verticillatum
Coral-necklace
Impatiens glandulifera
Indian Balsam
Impatiens noli-tangere
Touch-me-not Balsam
Imperata
Inula conyzae
Ploughman's-spikenard
Inula helenium
Elecampane
Iris foetidissima
Stinking Iris
Iris pseudacorus
Yellow Iris
Isolepis setacea
Bristle Club-rush
Jacobaea aquatica
Marsh Ragwort
Jasione montana
Sheep's-bit
Juglans regia
Walnut
Juncus acutus
Sharp Rush
Juncus bulbosus
Bulbous Rush
Juncus compressus
Round-fruited Rush
Juncus inflexus
Hard Rush