| Family | Scientific Name | Common Name | Habitat | Distribution | Image |
|---|---|---|---|---|---|
| Onagraceae | Chamaenerion | Fireweed |  | ||
| Onagraceae | Circaea | Enchanter's-nightshade |  | ||
| Onagraceae | Epilobium | Willow-herb) [also see Chamerion] |  | ||
| Onagraceae | Ludwigia | Seedbox, Water-primrose, Water-purslane |  | ||
| Onagraceae | Oenothera | Evening-primrose |  |