| Hairy Canary Clover |
Dorycnium hirsutum |
 |
| Hairy Chervil |
Chaerophyllum hirsutum roseum |
|
| Hardy Amaryllis |
Rhodophiala andicola |
 |
| Hardy Gloxinia (many) |
Incarvillea |
|
| Harebell |
Campanula rotundifolia |
 |
| Hawk's Beard |
Crepis |
 |
| Hawthorn |
Crataegus monogyna |
 |
| Heartleaf Ice Plant |
Aptenia cordifolia |
|
| Heartsease, Johnny Jump-up |
Viola tricolor |
|
| Hebenstretia |
Hebenstretia dentata |
|
| Hedgehog Broom |
Erinacea anthyllis |
|
| Heliconia |
Heliconia revoluta |
|
| Hellebore |
Helleborus orientalis |
|
| Herb Bennet |
Geum urbanum |
|
| Herb Robert |
Geranium robertianum |
|
| Herbert's Iris |
Herbertia pulchella |
|
| Hibiscus (many) |
Hibiscus |
|
| Hibiscus, (US) Rose of Sharon |
Hibiscus syriacus |
|
| Himalayan Honeysuckle |
Leycesteria formosa |
|
| Himalayan Indigo |
Indigofera gerardiana |
|
| Himalayan Indigo |
Indigofera heterantha |
|
| Himalayan Poppy (many) |
Meconopsis |
|
| Himalayan Poppy |
Meconopsis betonicifolia (alba) |
|
| Himalayan Poppy |
Meconopsis horridula |
|
| Hollyhock |
Alcea rosea |
|
| Honesty |
Lunaria annua |
|
| Honey Locust |
Gleditsia triacanthus |
|
| Honeysuckle |
Lonicera periclymenum |
|
| Honeywort |
Cerinthe major purpurascens |
|
| Hop |
Humulus lupulus |
|
| Hop Hornbeam |
Ostrya carpinifolia |
|
| Horsetail Tree |
Casuarina equisetifolia |
|
| Hot Water Plant |
Achimenes 'Palette' |
|
| Hyacinth Bean |
Lablab purpurascens, Dolichos lablab |
|
| Hyssop |
Hyssopus officinalis |
|
