| Halimium lasianthum (AGM) |
| Halimium ocymoides (algarvensis) (AGM) |
| Halimium 'Susan' (AGM) |
| Hamamelis x intermedia 'Arnold Promise' (AGM) |
| Hamamelis x intermedia 'Jelena' (AGM) |
| Hamamelis x intermedia 'Pallida' (AGM) |
| Hamamelis x intermedia 'Westerstede' |
| Hamamelis mollis (AGM) |
| Hebe albicans (AGM) |
| Hebe 'Autumn Glory' |
| Hebe 'Baby Marie' |
| Hebe 'Bowles's Hybrid' |
| Hebe brachysiphon |
| Hebe carnosula |
| Hebe 'Charming White' |
| Hebe 'Emerald Green' (syn.'Green Globe') (AGM) |
| Hebe x franciscana 'Variegata' (AGM) |
| Hebe 'Great Orme' (AGM) |
| Hebe 'Kirkii' |
| Hebe 'Marjorie' |
| Hebe 'Margret' |
| Hebe 'Midsummer Beauty' (AGM) |
| Hebe 'Mrs Winder' (AGM) (Waikiki) |
| Hebe 'Nicola's Blush' |
| Hebe ochracea 'James Stirling' (AGM) |
| Hebe odora 'Wintergreen' |
| Hebe 'Pewter Dome' (AGM) |
| Hebe pimeleoides 'Quicksilver' (AGM) |
| Hebe 'Pink Elephant' |
| Hebe pinguifolia 'Pagei' (AGM) |
| Hebe pinguifolia 'Sutherlandii' |
| Hebe recurva |
| Hebe 'Red Edge' (AGM) |
| Hebe subalpina |
| Hebe topiaria |
| Hebe vernicosa |
| Hebe 'Wiri Charm' |
| Hebe 'Wiri Image' |
| Hebe 'Wiri Mist' |
| Hebe 'Youngii' ('Carl Teschner') |
| Helichrysum italicum serotinum |
| Hibiscus syriacus 'Dorothy Crane' |
| Hibiscus syriacus 'Hamabo' (AGM) |
| Hibiscus syriacus 'Lenny' |
| Hibiscus syriacus 'Meehanii' |
| Hibiscus syriacus 'Oiseau Bleu' ('Blue Bird') (AGM) |
| Hibiscus syriacus 'Pink Giant' (AGM) |
| Hibiscus syriacus 'Red Heart' (AGM) |
| Hibiscus syriacus 'Woodbridge' (AGM) |
| Hibiscus syriacus 'William R. Smith' |
| Hippophae rhamnoides (AGM) |
| Holodiscus discolor |
| Hydrangea arborescens 'Annabelle' (AGM) |
| Hydrangea aspera sargentiana (AGM) |
| Hydrangea aspera 'Villosa' (AGM) |
| Hydrangea macrophylla 'Ami Pasquier' (AGM) |
| Hydrangea macrophylla 'Ayesha' (AGM) |
| Hydrangea macrophylla 'Gnle.Vicomtesse de Vibraye' (AGM) |
| Hydrangea macrophylla 'Hamburg' |
| Hydrangea macrophylla 'King George' |
| Hydrangea macrophylla 'Libelle' |
| Hydrangea macrophylla 'Lanarth White' (AGM) |
| Hydrangea macrophylla 'Mariesii' |
| Hydrangea macrophylla 'Madame Emile Moullière' (AGM) |
| Hydrangea macrophylla 'Mariesii Perfecta' |
| Hydrangea macrophylla 'Masja' |
| Hydrangea macrophylla 'Mowe' syn('Geoffrey Chadbund') (AGM) |
| Hydrangea macrophylla 'Pia' |
| Hydrangea macrophylla 'Quadricolor' |
| Hydrangea macrophylla 'Teller Blau' |
| Hydrangea macrophylla 'Tokyo Delight' |
| Hydrangea macrophylla 'White Wave' (AGM) |
| Hydrangea paniculata 'Grandiflora' (AGM) |
| Hydrangea paniculata 'Kyushu' (AGM) |
| Hydrangea paniculata 'Pink Diamond' |
| Hydrangea 'Preziosa' (AGM) |
| Hydrangea quercifolia (AGM) |
| Hydrangea serrata 'Bluebird' (AGM) |
| Hypericum androsaemum variegatum 'Gladis Brabazon' |
| Hypericum calycinum |
| Hypericum frondosum 'Sunburst' |
| Hypericum 'Gemo' |
| Hypericum 'Hidcote' (AGM) |
| Hypericum 'Hidcote Variegated' |
| Hypericum x moserianum (AGM) |
| Hypericum x moserianum 'Tricolor' |