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Lobelia siphilitica

Native Plants

Great Blue Lobelia

3 Photos


Great blue lobelia (Lobelia siphilitica) heralds the end of summer with its showy, blue flowers, borne on 1-3’ tall stems. This native perennial is a must for the naturalized garden. Great blue lobelia flourishes in moist soil with filtered shade but will adapt to drier conditions with more shade, and tolerates acidic to neutral conditions. This herbaceous plant is easy to grow from seed and frequently self-sows. Lanceolate serrated leaves alternate along the stem, culminating into tiny bracts amidst the bell-shaped blooms.  Grow great blue lobelia with white wood aster (Eurybia divaricata), purple turtlehead (Chelone obliqua), and hollow-stem Joe-pye weed (Eutrochium fistulosum), as they enjoy the same cultural conditions and will provide varying heights in the perennial border. Zones 4-9. 

More Details

  • Plant Type
  • Sun/Shade Conditions
  • Foliage Character
  • Soil Moisture
  • Flowering Period
  • Soil PH
  • Flower Color
    blue, purple 
  • Summer Foliage Color
  • Fall Foliage Color
  • Fruit/Seed Color
    green, tan