Helminthotheca echioides
Bristly Oxtongue
Helosciadium inundatum
Lesser Marshwort
Helosciadium nodiflorum
Fool's-water-cress
Hepatica nobilis
Liverleaf
Heracleum mantegazzianum
Giant Hogweed
Heracleum sphondylium
Hogweed
Hesperis matronalis
Dame's-violet
Hieracium anglicum agg.
Hawkweed (anglicum agg.)
Hieracium argillaceum
Southern Hawkweed
Hieracium cillense
Craig y Cilau Hawkweed
Hieracium lanatum
Hieracium maculatum
Spotted Hawkweed
Hieracium prenanthoides
Rough-leaved Hawkweed
Hieracium repandulare
Hieracium sect. Oreadea
Hieracium sect. Sabauda
Hieracium sect. Vulgata
Hieracium spp
Hieracium subbritannicum
Himantoglossum hircinum
Lizard Orchid
Hippocrepis comosa
Horseshoe Vetch
Hippophae rhamnoides
Sea-buckthorn
Hippuris vulgaris
Mare's-tail
Hirschfeldia incana
Hoary Mustard