Toxic Plant Known to be toxic - Toxic to mammals if ingested.
Image of Lobelia siphilitica
image of Flowering plant
Lobelia siphilitica
Great blue lobelia
Lobélie bleue

Obsolete Names

  • blue cardinal flower
  • great lobelia
No seeds available for this plant.

We are not accepting seeds for this plant at the moment.

Bloom colour: Blue Bloom period: July - September
Max Height: 3.0 feet
Max Width: 1.5 feet (spreads by rhizome)
Light condition:
Full sun More than 6 hours of direct sun a day
Part shade More than 2 or 3 hours but less than 6 hours of direct sun a day
Soil conditions:
Moisture medium Tolerates medium soil condition
Lifespan : Perennial
Gardener Experience:
beginner friendly Suitable for beginner gardeners
does not spread Does not spread uncontrollably
plant germinate easy Easy to germinate
Landscape uses:
wetland garden Suitable for wetland garden
rain garden Suitable for rain gardens
shoreline_rehab Suitable for shoreline rehabilitation
container suitable Suitable for container garden
school garden Suitable for school gardens
foot traffic tolerance light Tolerates light foot traffic
Ecological Benefits:
Hummingbird friendly Supports hummingbirds
Bird friendly Supports birds
Pollinator garden Supports pollinators
Tolerates:
Deer Resistant Deer resistant
rabbit resistant Rabbit resistant
limestone Tolerant Tolerates limestone conditions
boulevard garden tolerant Tolerates boulevard garden conditions
juglone Tolerant Tolerates juglone conditions
transplantation Tolerant Tolerates transplantation

Plant Distribution

Native to Ottawa region: Yes

Distribution according to VASCAN

Distribution: Lobelia siphilitica
Ephemeral Native Introduced Excluded Extirpated Doubtful Absent
View taxonomy on Canadensys

View on iNaturalist

Thrives in Ecozones

  • Ecozone-Mixed Wood Plain
  • Ecozone-Boreal Shield

Butterflies Supported by Lobelia siphilitica

  • Epargyreus clarus (Silver Spotted Skipper)

Bees Supported by Lobelia siphilitica

No bee data available for this plant.

Complementary Plants Plants that grow in similar conditions, that bloom at the same time.

  • No complementary plants found.

Sowing Information

  • Sowing depth: Surface sow
  • Sow before February
  • Stratification duration: 60 days
  • Self-seeding

Harvesting Information

  • Harvesting indicator: Pods are brown, seeds are dark, and crisp, and little stem connecting the pod to the main stem is brown (not green)
  • Harvesting mean: Cut stem (including pods), let air dry in paper bag, then shake seeds off after a few days
  • Seed Viability Test: No test needed before donating
  • Packaging Measure: Half of one, 1/32 teaspoon
  • Seed Storage: Air Dry in paper bag or open container, for a few days until crisp, shaking seeds to move them once in a while to prevent molding
  • On Cultivar: Yes, do not donate unless you know source, and there are no known cultivars in your garden or at proximity