Blue Cardinal Flower
Lobelia siphilitica
Rich blue-violet spikes that bloom right beside cardinal flower in late summer. Longer-lived, bumblebee-friendly, and happy in moist soil.
Typically 1 pint–1 gal · $9–$30 · final price at pickup
- Thu, Aug 138 AM – 4 PM
- Fri, Aug 148 AM – 4 PM
- Sat, Aug 158 AM – 2 PM
The perfect companion to Cardinal Flower. same height, same bloom time, same moist site requirements, with blue-violet spikes that serve a broader range of pollinators including bumblebees.
Blue Cardinal Flower partners perfectly with its red-flowered sibling, blooming at exactly the same time with the same upright habit and the same preference for moist soil. The rich blue-violet flower spikes are intensely saturated and hummingbirds visit them alongside the scarlet cardinal flower in a late-summer combination that's hard to beat. Plant both together along a stream edge or rain garden margin for a mid-border display that runs for weeks. It's longer-lived than Lobelia cardinalis in garden conditions and tends to form more substantial clumps over time. The white-striped blue flowers are more accessible to bumblebees than the hummingbird-tuned cardinal flower, so the blue species serves a broader pollinator audience. Self-seeds modestly in moist conditions. A garden classic for good reason.
A nursery-grown plant, ready for the ground.
Healthy, container-grown blue cardinal flower propagated on-site at Hill House from regional genetics. Includes a one-page care card. We make every effort to supply plants as listed; occasionally we substitute a similar species of equal value.
- Sun
- Full sun
- Water
- Moist
- Mature size
- 2–4 ft · 12–18 in wide
- Bloom time
- August–October
- USDA zones
- 4–8
- Family
- Campanulaceae
- Native range
- Eastern North America. moist woods, stream banks, wet meadows from New England to South Dakota south to North Carolina and Texas
Care notes for blue cardinal flower.
Plant in partial shade to full sun in consistently moist to wet soil. Similar care to Lobelia cardinalis. consistent moisture is essential and drought will cause rapid decline. Blue Cardinal Flower is somewhat more shade tolerant and longer-lived than the red species. Divide clumps every two to three years to maintain vigor. Allow some self-seeding for naturalization. Remove spent spikes to encourage additional blooms.
Pairs well with these.
Same light, same soil, same wildlife. Janet's picks to plant alongside blue cardinal flower.
Or skip the guesswork.
Curated packages bundle complementary species for an instant habitat. One reservation, one pickup day, a printed layout map.
Short on Space Package
For gardeners who have an abundance of passion but are short on space, this package features tidy, upright, clump-forming natives that behave and function well in small spaces.
Shade Bed Package
Ferns, sedges, and woodland natives that thrive under existing trees.
Birder’s Paradise Package
For the avid bird watchers and budding ornithologists in our community, the Birder’s Paradise Package consists of species that Hill House Nursery staff and longtime native plant advocates such as Doug Tallamy consider ‘premier bird garden plants’.