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Great Lobelia Lobelia siphilitica


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Great Lobelia - habit
credit: pris.sears/CCSA

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Alternate name: Great Blue Lobelia

Family: Campanulaceae, Bellflower view all from this family

Description Showy, bright blue flowers are held in the axils of leafy bracts and form an elongated cluster on a leafy stem. This Lobelia differs by its inch long blue flowers and its sepals cleft about halfway down the cup.
Habit: native perennial herb; stems erect, usually branched, us hairy, with milky sap.
Height: 1-4 ft (0.3-1.2 m).
Leaf: alternate, stalkless, narrowly oblong to elliptic, pointed, tapered base, toothed, smooth or hairy, 2-6 in (5-15 cm) long, 0.4-1.2 in (1-3 cm) wide; becoming fewer, smaller above.
Flower: dark blue to violet to lavender (rarely white), 5-parted, to 0.6-1.25 in (16-30 mm) long; 2 smaller upper petals, 3 larger lower petals; in long cluster along stem, to 10 in (25 cm) long.
Fruit: inconspicuous capsule, spherical, 0.25 in (6 mm) diameter.

Warning The root of this species contains alkaloids that cause vomiting. The leaves and seeds of some Lobelias also contain poisonous substances, and no parts of this plant should be ingested. Sensitivity to a toxin varies with a personís age, weight, physical condition, and individual susceptibility. Children are most vulnerable because of their curiosity and small size. Toxicity can vary in a plant according to season, the plantís different parts, and its stage of growth; and plants can absorb toxic substances, such as herbicides, pesticides, and pollutants from the water, air, and soil.

Flower August to October.

Flower July - October

Habitat Moist to wet sites; stream banks, wet meadows, low woods, around ponds and lakes, swamps, wet prairies, sloughs, roadside ditches; also cultivated as an ornamental.

Range Northeastern and north-central North America; Maine to Georgia, west to Texas, northwest to Colorado and Wyoming, northeast to the Dakotas and Manitoba, east to Ontario.

Discussion Also known as big blue lobelia, great blue lobelia, blue lobelila, blue cardinal-flower; a wetland indicator. Two varieties are proposed. This plant is endangered or vulnerable in Maine, Massachusets, and New York. The leaves and stems are browsed upon by white-tailed deer. This blue counterpart of the Cardinal Flower (Lobelia cardinalis) is a most desirable plant for woodland gardens especially since it blooms bright blue in late summer. The unfortunate species name, siphilitica, is based on the fact that it was a supposed cure for syphilis.

Exposure Preference Partial shade.

Native Distribution Connecticut to extreme s.e. North Dakota & Goshen County, Wyoming, s. to Georgia uplands, Texas & Colorado

Site Preference Open, wet woods; stream banks; marshes; meadows

Soil Preference Moist soils.