Ba
- Ballota
- X Ballota nigra
- Balsamita
- X Balsamita major
- Baptisia
- X Baptisia australis
- N Baptisia tinctoria — yellow wild-indigo
- Barbarea
- N Barbarea orthoceras — erect-fruit wintercress
- X Barbarea vulgaris — yellow rocket, common wintercress
- Bartonia
- N Bartonia paniculata subsp. paniculata — twining screwstem, branched bartonia Threatened
- N Bartonia virginica — yellow screwstem, yellow bartonia
- Bartsia
- N Bartsia alpina — velvetbells, alpine bartsia
- Bassia
- X Bassia hyssopifolia
Read more about this topic: List Of Canadian Plants By Genus B