Plant types and subtypes: Perennials
Light Requirements: sun, part-sun, part-shade, shade
Water Use: medium, high
Soil Moisture: moist, wet
Soil Description: rich, loam, clay, sand
Bloom Time: July, August, September
Bloom Color: blue
Leaf Color: green
Hardiness Zone: 4, 5, 6, 7, 8
Additional Tags: attracts bees, attracts butterflies, attracts hummingbirds, clumping, cottage garden plant, deer resistant, naturalizing, pond margin plant, stream margin plant, swamp plant
Pricing & Availability
Lobelia siphiliticaAlso known as:
great blue lobelia,
Lobelia siphilitica is a perennial wildflower with showy bright-blue flowers. It is an erect, typically unbranched plant that tops off at a height of 4' under ideal conditions. The tubular flowers develop from the leaf axils of the upper third of the stems, creating a dense blue spike. The leaves are alternate, and elliptical with serrated margins.
Lobelia siphilitica will adapt to full sun and open shade alike, in soil that is kept consistently moist. So long as the moisture requirement is met, it is very easy to grow and will thrive in both high quality, and degraded areas. It can spread from seed under ideal conditions, but is not an aggressive species. Because it is well behaved and very adaptable, it can be combined with a wide variety of wildflowers in perennial gardens and in wild, naturalized settings. It has a long blooming period that lasts about 2 months, and occurs from mid-summer to early fall. Zones 4-8
Propagate by division of mature clumps in spring. Sow fresh seeds in fall. Stored seeds do not require cold stratification before sowing, though doing so can improve germination rates.
Great blue lobelia is an excellent source for nectar and pollen, and will attract bees, butterflies and hummingbirds. The botanical name siphilitica stems from an early belief that this plant could be used to cure syphilis. All parts of the plant are poisonous if ingested in large quantities.
Native Range & Classification
Recorded County Distribution: USDA data
AR, CO, CT, DC, DE, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, ND, NE, NH, NJ, NY, OH, OK, PA, SC, SD, TN, TX, VA, VT, WI, WV, WY
USDA Endangered Status:
- Endangered: MA
- Exploitably Vulnerable: NY
|Species||Lobelia siphilitica||great blue lobelia|