Cardinal Flower
Lobelia cardinalis
Family Campanulaceae
There is no deeper red in the native palette than cardinal flower — scarlet spikes, two to four feet tall, in a shade so saturated it seems lit from inside. The tubular blooms fit a hummingbird's bill exactly, and hummingbirds patrol them like they know it.
A streambank native, it belongs where the ground stays moist — a pond edge, a rain garden, the low wet spot you never solved. Individual plants are short-lived but self-sow to stay. Deer skip it, and it isn't for eating anyway; plant it for the hummingbirds and stand back.
Full Sun to Part Shade
High water
Moderate growth
Deer-resistant
Native to North America
Attracts hummingbirds
Attracts bees
From the print shop
Growing cardinal flower? Hang it.
Our Plant Library collection carries cardinal flower — Lobelia cardinalis, print Nº 93, “Cardinal Flower.”
526 designsfrom $12.99white or black backgroundmatte poster, unframed
Will it thrive where you are?
Enter your ZIP — we look up your USDA hardiness zone (2023 map) and check it against what cardinal flower actually needs.
Hardy inZones 3-9Cardinal Flower · Common problems
Common cardinal flower problems
Pests
1 problem on file
- Almost none
Diseases
2 problems on file
- Rot if crown stays wet in winter (moist yes, stagnant no)
- Southern Blight
Cardinal Flower · Growing & propagation
Growing cardinal flower
- Light
- Full Sun to Part Shade
- Water
- HIGH
A streambank native; never let it dry out
Soil- Rich, constantly moist to wet · pH 6.0 - 7.0
Fertilizer- Light compost
Pruning- Leave a few to self-sow; cut others
Short-lived (2-3 yrs) but self-sows if the soil stays moist and open; let some seed. Keep the crown from being smothered by mulch/leaves.
Spacing- 12-15 in
How to plant & propagate cardinal flower
- Propagate
- Division or seed
Cardinal Flower · Calculators & field guides
A little help in the garden.
Cardinal Flower · Yearly calendar
The cardinal flower year, month by month
Jan
No calendar activity is listed for this month.
BloomBloomJuly to September
What each band means
- Bloom — flowers open — pollinators working, frost on blossoms is the danger.
These are the species' typical months — expect them a few weeks earlier in warm zones and later in cold ones. Watch the plant, not just the calendar.
Cardinal Flower · Ecology & uses
Ecology & uses
Lobelia cardinalis
Cardinal Flower in the garden system
- Herbaceous layer perennial
- Nectary/insectary
Attracts- Hummingbirds, Bees
Habitat- Wetland
Moisture- Wetland / wet-tolerant
- Deer
- Resistant
A safer unfenced choice
- Origin
- Native to North America
What cardinal flower is grown for
⚠ Toxic if eatenToxic if eaten
Use- Hummingbirds
- Use
- Rain gardens
- Use
- Pond edges
Edibility, identification, and traditional-use notes here are general reference — not medical or veterinary advice, and not a claim that any plant treats or prevents anything. Medicinal ratings record how strongly a plant features in herbal tradition, nothing more. Never eat or dose a plant you have not positively identified. More on how to use this library.
Cardinal Flower · Varieties & cultivars
Choosing a cardinal flower variety
'Cardinalis' (native scarlet); 'Black Truffle' (dark foliage); Lobelia × 'Grape Knee-High'
Sources & plant identity
Know what you’re growing.
See where the knowledge comes from.
Cardinal Flower
Lobelia cardinalis
The plant, at a glance.
- Botanical name
- Lobelia cardinalis
- Plant family
- Campanulaceae
- Growth habit
- Perennial
- Origin
- Native to North America
- USDA plant symbol
- LOCA2
- Invasive risk
- Low
Hardiness, size and timing vary with your cultivar, soil and climate.
Rooted in research.
University extension research, brought together with hands-on growing experience at Story Thyme Farms.
Questions
Cardinal Flower questions, answered straight.
Do deer eat cardinal flower?
Rarely — cardinal flower is considered deer-resistant, which makes it one of the safer unfenced choices in deer country. Hungry deer in a hard winter test every rule, but it's a low-risk pick.
Is cardinal flower safe for kids and pets?
No — treat it as toxic if eaten. Toxic if eaten Site it accordingly if children or pets roam the garden. This is general reference, not medical or veterinary advice — call a vet or poison control if something has actually been eaten.
How do you propagate cardinal flower?
Division or seed.
Elsewhere
Where cardinal flower sits in the library.
Sunflower
Zinnia
Peony
Daylily