| NAME OF PLANT | WHERE FOUND | DATE | WHERE FOUND | DATE |
| Hedera helix | ||||
| ivy | ||||
| Helianthemum numularium | ||||
| common rock-rose | ||||
| Helictotrichon pratense | ||||
| meadow oat-grass | ||||
| Helictotrichon pubescens | ||||
| downy oat-grass | ||||
| Helleborus foetidus | ||||
| stinking hellebore | ||||
| Helleborus viridis | ||||
| green hellebore | ||||
| Heracleum mantegazianum | ||||
| giant hogweed | ||||
| Heracleum sphondylium | ||||
| hogweed | ||||
| Hesperis matronalis | ||||
| dame's violet | ||||
| Hieracium agg. | ||||
| hawkweed | ||||
| Hippocrepis comosa | ||||
| horseshoe vetch | ||||
| Hippophae rhamnoides | ||||
| sea buckthorn | ||||
| Hippuris vulgaris | ||||
| mare's-tail | ||||
| Hirschfeldia inacana | ||||
| hoary mustard | ||||
| Holcus lanatus | ||||
| Yorkshire fog | ||||
| Holcus mollis | ||||
| creeping soft-grass | ||||
| Honckenya peploides | ||||
| sea sandwort | ||||
| Hordeum murinum | ||||
| wall barley | ||||
| Hordeum secalinum | ||||
| meadow barley | ||||
| Hottonia palustris | ||||
| water-violet | ||||
| 41 | ||||