Common name: Great blue lobelia
Botanical name: Lobelia siphilitica
Virtues: Blooms in late summer. Flowers are lavender to deep blue. Related to cardinal flower (Lobelia cardinalis), which has similar flowers in red.
Flowers: Tubular flowers on 2- to 3-foot tall stems. Lavender to deep blue in color.
Habit: Clump-forming herbaceous perennial, 2 to 3 feet tall and 1 foot wide.
Season: Late summer, for flowers.
Origin: Wet woods, stream banks and marshes from Connecticut through the Midwest, lower Great Plains and upper South.
Cultivation: Tolerates a wide range of light level, from full sun to shade. Most tolerant of full sun in cooler climates. Requires wet or moist soil. Forms clumps that can be divided and sometimes spreads itself by seed. Easy to grow if provided the damp conditions it prefers. USDA Zones 4 to 9.
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